Rhubarb Crumble Bars
from https://www.ifyougiveablondeakitchen.com/

Bake a tart, yet buttery, dessert bar this summer. Made with chewy oats, these rhubarb crumble bars are easy to make from scratch. They’re a delicious treat to bring to barbecues and picnics!

Tips:

• Cook filling until thickened. If the mixture is too water it will make the bars soggy. It should coat the back of a spoon and be thick like fruit preserves.
• Cool completely before serving. This is an important step to ensure the bars set up properly and aren’t messy.

To make in a 9x9 inch pan, increase ingredients by 1/4 more.

Crust and Topping
1 1/2 cups (187 g) all purpose flour
1 1/2 cups (150 g) rolled oats
1/3 cup (66 g) packed light brown sugar
1/3 cup (66 g) granulated sugar
1/4 teaspoon baking powder
1/4 teaspoon salt
3/4 cup (12 Tablespoons or 170 g) unsalted butter, softened, but still cool, cut into 1/2-inch pieces
1 teaspoon vanilla extract

Rhubarb Filling
2 cups (300 g) diced rhubarb
1/3 cup (100 g) granulated sugar
1 Tablespoon cornstarch, or flour
1 Tablespoon fresh lemon juice
Pinch of salt

Preheat oven to 350℉. Line a 8×8 baking dish with parchment paper and set aside.

In the bowl of a stand mixer (or using a hand mixer), combine flour, oats, brown sugar, granulated sugar, baking powder and salt. Mix for 30 seconds until thoroughly combined. With the mixer on low, add the butter and vanilla extract. Mix until the mixture resembles coarse sand (about 2 minutes).

Transfer half the mixture to prepared pan. Use your hands or the back of a measuring cup to press mixture evenly into the bottom to form the crust. Bake crust for 20 minutes or until golden (keep the oven on).

While the crust bakes, make the rhubarb filling. In a saucepan over medium heat, bring rhubarb, sugar, cornstarch, and lemon juice to a boil. Stir constantly until mixture is thickened, about 2 minutes. Remove from heat. Cool slightly. [Don't overcook so there are some chunks left.]

Spread rhubarb mixture over baked crust. Sprinkle remaining oat mixture evenly over the fruit layer.

Bake bars for 30 to 35 minutes or until the rhubarb bubbles and the top is golden brown. Allow bars to cool completely before removing from pan and cutting into 16 squares.

Makes 8x8 inch pan - 16 bars