Thursday, May 19, 2011

Strawberry-Rhubarb Crostata

One of my favorite dessert flavors is the combination of strawberries and rhubarb. I always look forward to this time of year when both are abundant and I can make strawberry-rhubarb desserts to my heart's content. The combination of these two fruits makes one of the finest crisps imaginable and of course Strawberry-Rhubarb Pie is a classic. Last year I posted a new favorite—Strawberry-Rhubarb Bavarian. This year, I thought I would share my recipe for a Strawberry-Rhubarb Crostata.

A crostata is a flat, "free-form", rustic tart. It is sometimes called a galette. In the world of seasonal desserts, it is hard to imagine a dessert with more charm that can also be pulled together on short notice with a great deal of ease. Less fussy than a double crust fruit pie (a fruit pie has to "set up" for a few hours before it can be consumed, while a crostata only needs to sit for 20 minutes or so) and more elegant than a crisp (a crostata slices beautifully for serving), if you keep rounds of crostata dough in your freezer, you can easily prepare a fresh fruit crostata for an impromptu dessert with whatever fruit you find at the market.  

In theory, if you can make the crust, a crostata is the easiest of desserts to make. Just roll out the crust, fill with fruit that has been sweetened to taste, fold the edges of the crust up and over the fruit and bake in a hot oven. In actual practice, fruit crostatas can be a bit tricky. When made with fruits that tend to be very juicy or that require a lot of sugar, the baking fruit can produce more sugary fruit juices than the casual crust can contain. Crostatas that experience a "blow out" in the oven are quite unattractive.

The main reason a small leak in the crust can create a minor disaster is that traditionally crostatas don't have any added thickener. The idea behind this is that the wide, open surface of the crostata should allow the fruit juices to evaporate and concentrate as the tart cooks, making a thickener unnecessary.   Unfortunately, it doesn't always work this way.  If the unthickened juices begin to escape, there is no stopping the flow.  Because the fruit flavor without thickener is so pure and clean, for years I resisted adding any. But I have finally come to the conclusion that a small amount of cornstarch or flour is not the worst thing in the world. Certainly it is better than having a bottom crust that is soggy and gummy rather than crisp and flaky. It is also better than having all of your beautiful fruit juices flow out of the crust and into the pan (or worse yet, the floor of the oven) where they will burn.

Another less-than-traditional addition to my Strawberry-Rhubarb Crostata is the oatmeal streusel that I scatter over the surface of the fruit. Crostatas are frequently made with large chunks of fruit that maintain their shape as they bake and are beautiful to look at in the finished tart. Strawberries and rhubarb both collapse into a chunky compote as they bake. While not unattractive, it isn't particularly lovely, so covering up the fruit with a sweet and crunchy streusel adds (I especially like rhubarb with streusel) without taking away.

I love the strawberry-rhubarb version of this dessert. If you, or someone you know, loves the combination of strawberries and rhubarb, you should give this recipe a try. Apparently it is so good that it is irresistible. Several years ago while working at a private event facility I made miniature, individual-sized crostatas for a spring event. The party turned out to be smaller than expected and there were several tartlets left over. Since I happened to know that the husband of a friend and co-worker loved strawberry-rhubarb desserts, I sent two tarts home with my friend for the two of them to enjoy.

A week or two later I was having dinner with them when I decided to ask her husband how he had liked his strawberry-rhubarb crostata. My query was met with a puzzled look, accompanied by a "What strawberry-rhubarb crostata?".  As I opened my mouth to reply, I received a sharp kick to the shins under the table. But it was too late. To this day I am occasionally reminded of what a big mouth I have as we laugh about the time my friend was unable to resist the call of the second tart as she drove home from work that day. Since she tells me that "they were so small....hardly big enough for one serving..." you should just make one large crostata. That way everyone will be able to cut as large a slice for themselves as they please.


 Strawberry-Rhubarb Crostata

1 recipe of Crostata/Galette Dough
3/4 lb. rhubarb, trimmed and sliced cross-wise into a 1/2-inch pieces
1 pint strawberries, washed and hulled and halved (quartered if large)
1/4 c. sugar
2 T. cornstarch
1/4 c. Strawberry preserves, well stirred
1 recipe Crumb Topping

On a lightly floured board, roll the dough into a 14-inch round about 1/8-inch thick. Place the round on a parchment lined cookie sheet (preferably without a rim). Chill the round of dough for at least 30 minutes.  

When you are ready to build the crostata, place the fruit in a large bowl. In a small bowl, whisk together the sugar, cornstarch and a pinch of salt. Add the dry ingredients to the rhubarb and strawberries and toss to coat.

Spread the preserves over the chilled round of dough—leave about 3 inches of dough all around.

Top with the fruit mixture. Mound the crumb topping over the fruit.

Fold the edge of the dough up onto the fruit, pleating it attractively and pressing lightly as you go.

Place the crostata in a 450° oven either on the lowest rack or on a pizza stone. Bake for 10 minutes. Reduce the temperature to 400° and continue to bake until the crust is golden and cooked on the bottom and the fruit is bubbling. Slide the baked crostata (with the parchment) off onto a wire rack to cool—don’t do this if your cookie sheet has a rim. Let cool at least 20 minutes before serving. Serve with whipped cream or vanilla ice cream. This Crostata is best served the day it is made. Serves 6 to 8.

Crostata/Galette Dough:
1 stick (4 oz.) unsalted butter, chilled and sliced 1/4-inch thick
1 c. plus 2 T.  (4 1/2 oz.) all purpose flour
2 T. sugar
1/4 t. salt
2 T. ice water

Place flour and butter in a food processor and pulse/process until mixture is in little pieces. Turn butter and flour mixture into a large bowl and add the sugar and salt. Toss to combine. Drizzle the ice water over the flour mixture. Using your hands (or a fork), fluff the mixture until it begins to clump. If, when you squeeze some of the mixture it holds together, the dough is finished. Turn the dough out onto a counter and form into a mound. Using the heel of your hand, gradually push all of the dough away from you in short forward strokes, flattening out the lumps. Continue until all of the dough is flat. Using a bench scraper, scrape the dough off the counter, forming it into a single clump as you do. Form the finished dough into a thick disk. Chill for at least 30 minutes.

Crumb Topping:
1/3 c. flour
6 T. packed brown sugar
pinch of salt
3 T. unsalted butter, chilled and cut into cubes
1/4 c. oatmeal

In a medium-sized bowl, combine the flour, sugar and salt. Rub in the butter until the mixture is crumbly. Add the oatmeal and toss to combine.


Katrina said...

Ha, great story about your friend!
I make crostatas every time I have any leftover pie dough. Even if I just throw a thinly sliced apple on the dough with a little sprinkling of sugar.
I need to start looking for rhubarb in the store and I need to plant some out here.
Have you ever used any other fruit with the rhubarb, or always strawberry--which I love, but was just wondering?
Oh how I miss your desserts (and everything else) at The Merc!

Paige said...

Hi Katrina! I bet that the leftover pie dough with a little fruit is how crostatas came about--because you can pretty much make them any size. I didn't mention it in my post, but you can much more easily get by without any thickener with miniature ones.

I usually just do rhubarb alone or with strawberries. But I think raspberries would be a good flavor partner too. I have also seen rhubarb combined with apples, but to me that seems odd because they are opposite seasons...

I hope you are doing well and that your weather is finally warming up for the year (and you have been able to find a convenient farmers' market or farm stand!).

Daphne said...

I have Rhubarb and Strawberries. Dan will love has everything he enjoys (including the crumb topping)! Hope all is well with you. My herb garden is in and is flourishing - Yay!! I will be decreasing my work hours to 24 per week effective June 6th. Thank was supposed to happen in January and then was put off until now. Long story. But better late than never.

Paige said...

Pam,I'm so glad you are going to have more time!

I think you (and Dan!) will enjoy the is the same template as the plum galette that I made for you and Dan when I cooked for your anniversary.

Anonymous said...

Why does my pie dough always crack and not form a near perfect circle? I make sure it is chilled. It rolls out all over the place with huge claws. I start in the middle and roll out and then turn a quarter, flour, and then roll out, etc.

Paige said...

I think the most common reason for cracking is that the dough is too cold. If you are rolling it right after removing it from the fridge, maybe let it sit on the counter for five minutes before starting to roll. Sometimes I use the warmth of my hand to warm up the edges: take the disc of dough and gently (and very briefly) squeeze the edge, rotating the disc until you have repeated this action around the entire perimeter of the dough.

Another possibility is that there isn't enough liquid in your dough and it is therefore too dry. If you're referring specifically to the crostata dough in this post, that's probably not the issue...this is such a high fat dough that it is more likely cracking because it's too cold.

Finally, you might take a look at my tutorial post on short crust pastry ( Maybe you already have... Anyway, it is a slightly different dough, but the "fraisage" step that I describe in that post contributes to dough plasticity and can help prevent cracking around the edges.

I hope this helps!

Anonymous said...

A question about whether the approach you used for the Rhubarb Coffeecake (overnight sugaring + quickly cooking the rhubarb with the juice over high heat) would work for this crostata. Or would the rhubarb just become a jam when the crostata cooks? I was thinking this might be an alternative to using a thickener.

Our rhubarb is just now ready to start harvesting, but no strawberries yet. So we're looking at a rhubarb only version. Might try it with strawberry ice cream, though!

Thanks in advance for the help. Kathy

Paige said...

Hi Kathy, Good question! I don't know how it would work...but I think it's a great idea and definitely worth a try. I think you'll find that you need a lot of rhubarb (since it will shrink before you put it in the tart)....and I don't think that it's the end of the world if it softens to a jam-like consistency as it cooks. It might be fun to make a rhubarb and frangipane crostata (like the peach-raspberry one I posted a few years back). This would allow you to use a bit less rhubarb...and you wouldn't need a streusel since you could arrange the rhubarb attractively over the frangipane.

If you try it, I would love to hear back how it works out for you. You could even post a picture of your result on my FB page so I can see it.

Thanks. Good luck!

I hope this helps.

Anonymous said...

Done and done! But with the following caveats.
* All rhubarb, no strawberries
* Instead of overnight, I just had 6 hours
* Rhubarb was cold (picked a couple of days ago) - seemed to slow the juicing
* Used your high-temp method to reduce the juice & pre-cook the rhubarb. Pulled the rhubarb just as it was starting to soften. Continued reducing the juice. Let it all cool.
* Being a worry-wart, I used 1 TBS cornstarch & 2 TBS fine bread crumbs (on top of the strawberry jam)

From the pix on Facebook, you can see all the blow-outs. The dough did not cooperate! But, fairly minimal leakage, despite seeing the first breach when reducing the temp at 10 minutes. So, I'm wondering if the saving graces were the cornstarch & the sugaring/liquid reducing step.

In any case, no galette went to waste -- just to waist!

Paige said...

Kathy, thanks so much for posting the picture. I'm sure the cornstarch and breadcrumbs helped. Alice waters scatters a mixture of equal volumes of ground almonds. flour, sugar and ground amaretti cookies over the bottom of her free from tarts...accomplishing the same thing as your breadcrumbs. (I have never done it because I don't keep amaretti on hand.) As for the dough...this dough is fragile and a bit touchy. I make savory free form tarts all the time with my standard pate works very well and would be fine for a dessert tart. It is flaky and tender...although not as tender as this one...and of course, not sweet at all. But then standard American pie dough is not sweet either.

I loved hearing about this. It was a good idea. I will have to try it.

Anonymous said...

Oh, sorry! The "uncooperative dough" comment was not a complaint. Just a report on this particular iteration. Your good tutorials have been a godsend with regard to making pie/tart/crostata dough. The dough recipe here has become the one I turn to over and over again -- accompanied by a silent "thank you" each time. Also appreciated are the ingredients by weight. I hope you enjoy creating the blog as much as we've enjoyed eating from it!

Paige said...

No need to apologize! I was simply acknowledging that this dough can occasionally be exactly as you put it...uncooperative. But I love it, so I continue to use it and posted it for others, knowing they would probably love it too.

I really do enjoy working on my blog....but appreciate it so very much when I hear back from someone that they are enjoying it too. Thank you!