These Strawberry Rhubarb Crumble Bars are a snap to make. The crust doubles as the crumble topping. Just make sure to dice the strawberry and rhubarb in to small 1/4-inch chunks, so that they turn into a jammy fruit center filling. Larger pieces of fruit will lead to a chunkier filling.
For the crust and crumble dough
3 cups (420 g) all-purpose flour
1 cup (200 g) white granulated sugar
1 teaspoon baking powder
1/2 teaspoon ground cinnamon
1/4 teaspoon kosher salt
1 cup (225 g or 2 sticks) unsalted butter, cold
1 large egg
For the fruit filling
2 cups (250 g) diced 1/4-inch chunks) rhubarb (2 to 3 thick stalks or 5 to 6 thin stalks or a little over 1/2 pounds)
2 cups (310 g) diced (1/4-inch chunks) strawberries (3/4 pounds)
3 tablespoons white granulated sugar
1 tablespoon cornstarch
1 tablespoon lemon juice
Preheat the oven to 375°F. Spray a 9x13-inch pan with cooking oil. Line the pan with parchment paper with the one inch of extra parchment paper hanging over the sides.
Make the dough:
Combine the flour, sugar, baking powder, cinnamon, and salt in a medium-sized bowl. Cut the butter into 1/2-inch chunks and sprinkle over the dry ingredients. Using your fingers, squish the butter, breaking it down into small bits and mixing the dry ingredients together. The butter should be the size of small peas, but flat, not in chunks.
Add the egg and toss together with a fork at first, then massage into the dough with your hand. The dough will be crumbly.
Divide the dough and shape the crust: Scoop 1 cup (about 170 g) of the crumbly dough and set it aside.
Dump the remaining dough into the bottom of the lined pan and press down on it firmly with your hands or with the flat bottom of a cup, to form an even layer of dough at the bottom.
Make the filling and add to the pan:
Combine all the ingredients in a bowl (you can use the same bowl you made the dough if you’d like, no need to clean it). Spread it out evenly over the bottom crust.
Top with crumbles and bake:
Sprinkle the reserved crumbly dough over the fruit filling. Bake in the oven 40 to 45 minutes, or until the top of the fruit is bubbling and the crumb topping is golden brown. Cool completely in the pan until it reaches room temperature.
Cool and cut the bars:
Use the side of the parchment paper to lift up and move the entire block carefully to a cutting board. Cut into bars. Serve at room temperature. Store in the refrigerator in an airtight container for 2 to 3 days.