Crust & Topping:
2 1/2 cups all-purpose flour
1/2 cup finely ground pistachios
1 cup sugar
1 tsp. baking powder
1/4 tsp. salt
Zest from 1 lemon
1 cup (16 tbsp) unsalted butter, cubed and chilled
2 tsp. vanilla extract
2 cups sliced rhubarb
2 cups sour cherries, stemmed, pitted and halved
1 tablespoon corn starch
Juice from 1/2 lemon
Preheat your oven to 375 degrees. Spray a 9 X 13-inch baking pan with non-stick cooking spray. Set aside.
In your food processor with the blade attachment, pulse together the flour, finely ground pistachios, sugar, baking powder, salt and lemon zest. Add the butter, egg and vanilla extract. Pulse until the dough resembles a course meal. Set aside.
In a large bowl, toss together the rhubarb, cherries, corn starch and lemon juice. Set aside.
Transfer about two-thirds of the dough into your prepared baking pan. Using your hands, press it down firmly into an even layer. Then spread the fruit mixture in a single layer over top. Sprinkle the remaining dough over the fruit.
Transfer the baking pan to your pre-heated oven and bake for 40-45 minutes, or until the top is lightly browned. Remove from the oven and set aside to cool completely before slicing and serving.
Leftovers can be stored in an airtight container in your refrigerator for 2-3 days.