I am eating at new places and baking so much that I just have un-ending amounts of posts to make. Before I blogged about rhubarb scones and honestly I bought way too much rhubarb last time so I had tons left over. Luckily, the tarts used up all the rhubarb, so now I can move on to new things!
Anyway, I work in a Biology research lab, and so I thought it would be nice to bake for our lab meetings. Usually the PI will bring in food, but I decided to bake anyway, and I think I get the honors to bake for them every week. =) That means there will be at least one baking update every week! This week I made rhubarb shortbread tarts.
When I was deciding what I wanted to make, I knew that I wanted my noms to be 1) finger food, so that it isn’t messy to eat during a meeting, and 2) I needed to use up my rhubarb. So I flipped through the rhubarb recipes at Saveur, and I found this, a rhubarb pie recipe. It was perfect because I didn’t have any strawberries or other types of fruit on hand. Then I thought about the texture and taste of rhubarb, and decided that instead of a normal flaky crust I wanted shortbread crust. I personally love shortbread, but I also felt like the sweetness would do wonders for the rhubarb’s tartness. So I went off to find a shortbread tart/pie/crust recipe, and stumbled upon this, caustic confit from Smitten Kitchen. I only used the crust recipe and ignored the rest. Finally, since I wanted finger food and since I had a 24 mini muffin pan, I decided to combine everything into mini tarts! I think they are the most adorable things ever.
For the filling:
- ¼ cups flour
- 2 tsp. kosher salt
- 4 cups chopped rhubarb into small pieces, roughly 3 stalks
- 1 cups sugar
- 1 tsp. vanilla extract
- 2 eggs
- 2 tbsp corn starch dissolved in some water
For the crust (probably half of this will be more than enough, but this is what I made):
- 3 cups flour
- 1 teaspoon salt
- 1/2 pound (2 sticks) cold unsalted butter, cut into 1-inch pieces
- 1 1/4 cups sugar
- 1 large egg
- 2 tablespoons water
- Combine flour, salt, sugar into a bowl and whisk to combine. Cut in the cold pieces of butter so that the dough is flaky and forms crumbs and clumps.
- Mix the egg and water together, and mix into dry ingredients until just incorporated. The dough will be very crumbly, but try to form it into a solid mass and wrap it into plastic wrap and refrigerate for at least 30 minutes.
- To make the filling, toss flour, all the salt, rhubarb, sugar (to make the filling not as sweet, I would recommend 1/4 cup sugar, see note), vanilla and eggs and whisk to mix. Dissolve the corn starch in water and add it to the bowl. Let the filling sit so that the water from the rhubarb can come out.
- Form your tart crust into the tart pan. I took a small piece of the dough (still very crumbly and cannot be rolled out), and smash it into a relatively thin disk. It should be as thin as possible without it coming apart when you try to lift it off the surface. Put the disk into the tart tray, and push against the bottom and sides. There should be extra dough due to the three dimensional shape, so rip it off and return that to the big pile of dough. Do this for all 24 holes. It will take a while because there are so many, so put plastic wrap on your dough to prevent it from getting even dryer.
- Do a blind bake of the tarts at 350F. I would suggesting docking the bottom of the crusts and hope that it doesn’t warp, but it doesn’t matter if it does. Bake for 3-5 minutes, just until it looks like it will hold its shape without browning or being fully cooked.
- Heat up your filling so that some of the corn starch can start to coagulate and make the filling less watery. I did this via a double-boiler method, and cooked it until it reached a egg-like consistency.
- When the tarts are back out, use just a little bit of dough to cover the bottom of the tart crusts. It should be about 2mm thick; just enough so that the filling doesn’t soak through the crusts while baking. Fill each crust with filling, using more of the rhubarb than the sweet liquid. I let my rhubarbs pile on top and only filled the liquid to just below the top of the tarts.
- Bake for another 10-15 minutes, until the edges are gold brown.
Note: The tart came out to be sweeter than I expected. I had envisioned a tart filling with sweet shortbread crust, but the filling was pretty sweet. If I were to redo this, I would definitely cut back to 1/4 cups of sugar, just enough to offset the rhubarb’s tartness.
So overall, I think the tarts were successful. In mid-baking, I was scared that the rhubarb filling wouldn’t solidify and I would end up with super runny tarts. After all, the filling was meant for a pie, and pie fillings are usually not completely solidified. I don’t know if it was the corn starch or the high surface area to mass ratio, but to my relief it did solidify. However, the filling was on the sweet side, which I really should have expected with one cup of sugar.
Also, I took tons of precautions to make sure the crust was crunchy. I really, really didn’t want a soggy tart, so I took an idea from way back when using a blind bake + an extra layer of crust on top of the blind bake. Cooking of the filing into something less runny was also a precaution I took for crunchy tarts. And indeed, the shortbread tarts were buttery and crunchy, from side to bottom, which I was very satisfied with.
A little preview: I will be making more shortbread because I stupidly followed the recipe for the crust to the dot, and ended up with tons of left over shortbread dough. I already know what I’m going to make for it, and I’m super excited. =)