Rhubarb is one of my favorite things on earth. And like Thanksgiving dinner, and corn on the cob, and egg nog, rhubarb is one of those elusive things you only have a certain time of year, thus adding to its appeal. There's nothing else quite like it in its tang, sweetness, and earthiness. My grandma's rhubarb pie is next level, and it's one of my life goals to perfect it in all its glory. This rustic crostata that I made with her pie crust is a good start.
Jon and I ate this for breakfast yesterday, and then again for dessert at a makeshift picnic we had at a nearby art gallery in the last couple hours of sunlight. It tastes so perfect in these late days of spring that feel like summer. And like many pies, it was even better after sitting on the counter top for a day.
Things I learned whilst baking this: a crostata and galette are essentially the same thing. Both refer to a rustic, free form pie, but crostata is Italian and galette is French. Good to know!
So, I went with crostata because of how fitting the name sounds for a crusty, tart-like pie.
2 cups flour
1 tsp salt
1 tsp sugar
¾ cup butter flavored shortening (I use Crisco), as freezing cold as possible (I store mine in the fridge, but throw it in the freezer for a half hour before)
4-8 T ice water (I just place several ice cubes in a small bowl of water)
Before beginning, it's most important to know that the goal is really to keep the mixture as cold as possible through this entire dough making process. This means working quickly, handling it as little as possible, and if need be, putting it back in the fridge in between steps to re-chill.
So, in a large bowl, sift or whisk together flour, salt, and sugar. Remove shortening from the fridge or freezer, and dice into small pieces. Add shortening pieces, in a spread out fashion, into the flour mixture (this is when, if I felt the shortening wasn't cold/firm enough, I'd throw the bowl in the fridge for 15 minutes or so just to chill it again). Then use a pastry cutter to cut through the mixture, all around the bowl, until the entire thing resembles a range of pebble sized pieces, some the size of peas, and some like little corn flake sized pieces. (The little pieces of cold butter/shortening in the dough are what you want—that's what expands with air in the oven and becomes flaky goodness!) Then add ice water (just water, NOT ice cubes), about 1 T at a time, using the pastry cutter again after each addition, scraping the pastry cutter off a bit when it gets too clogged. I usually find that about 6 T of water is a good amount, in total, but it is slightly different every time. You just want enough water for the dough to come together if you squeeze it between your fingers (you're not looking for a giant ball of dough—that would means it's too wet and overworked—it should just have the ability to come together when squeezed). And, at the same rate, when you go to turn it out of the bowl and onto plastic wrap, it will easily come together, without leaving a lot of crumbs behind—it's a uniform mixture that hasn't been formed yet, if that makes sense. So, fold the plastic wrap around it, using the plastic wrap to form it into a sort of disc. It doesn't have to be perfect. Make sure it's completely covered and folded, and place in fridge to chill for at least a half hour.
Pie filling & finish
3 heaping cups of ¼ inch slice rhubarb (about 4 stalks)
¾ cup white sugar
1 T lemon juice
½ tsp vanilla
2 T flour
Egg wash (1 egg beaten with about 1 tsp water)
1 T large granulated sugar crystals (otherwise just regular sugar—the large crystals just look so pretty) for sprinkling
1 T butter
Preheat oven to 375 degrees with the rack in the center of the oven.
In a medium bowl, combine rhubarb with sugar, lemon juice, and vanilla, and fold together until evenly incorporated. Sprinkle in flour and salt and stir together well again. Set aside for a few minutes (maybe 10-15 or so) to let it macerate.
Pull dough from the fridge (you'll want it to come to room temperature for 10 minutes or so). Meanwhile, place a large piece of parchment paper on your counter top. Sprinkle with a little flour, and set dough in the center of the parchment. Roll out dough into a large circle about ⅛ inch thick, adding flour if you need to to avoid sticking/tearing, and replacing any cracks with smaller pieces of dough. Pick up edges occasionally to ensure they're not stuck to the parchment. Then pick up the parchment and transfer to a rimmed baking sheet.
Use a spoon or your hands to place rhubarb mixture evenly in the center of the dough, in a slight mound, leaving about 2 inches all around. Leave behind excess liquid in the bowl. At this point, you can use a knife to cut the outside edge of crust into a more perfect circle if there seems to be more than a couple inches on any side.
Otherwise, just fold sections of the crust up over the rhubarb, overlapping a bit with the next section and pressing together those sides a bit, lightly, to secure it. It doesn't have to be/probably won't be perfect. This is a very rustic version of a pie! If you see any cracking, press together or patch with other tiny pieces of crust from the outer edge.
Then brush (or use your hands) to rub the entire crust with egg wash (you won't use even close to all of it—just coat want a thin layer on the entire crust). The egg wash can also be used to close up any seams, so still be aware of any cracking, especially along the bottom.
Then sprinkle crust with about half the tablespoon of sugar crystals, and then sprinkle rhubarb center with the other half. Dot the rhubarb with little pieces of the butter tab that you've cut apart or torn apart with your fingers.
Bake in the center of the oven for about 40 minutes (give or take 5 minutes, of course) until crust is golden and rhubarb is bubbling slightly. Remove from oven, set baking sheet on a wire rack, and let cool a while before serving (at least 45 minutes to an hour). Serve as is, or with vanilla bean ice cream.