01 - Preheat oven to 350°F. Line a 9x13-inch baking pan with parchment paper, allowing edges to overhang for easy removal later.
02 - In a large bowl, combine flour, oats, granulated sugar, brown sugar, baking powder, and salt. Mix well to distribute evenly.
03 - Pour melted butter and vanilla extract over the dry mixture. Stir until the mixture becomes crumbly and all ingredients are evenly moistened.
04 - Measure out and set aside 1 ½ cups of the crumb mixture for the topping. Press the remaining mixture firmly and evenly into the bottom of the prepared pan to create the crust layer.
05 - In a separate bowl, combine cherries, granulated sugar, cornstarch, lemon juice, and almond extract. Toss until cherries are evenly coated.
06 - Spread the cherry mixture evenly over the pressed crust in the pan.
07 - Sprinkle the reserved 1 ½ cups of crumb mixture evenly over the cherry layer.
08 - Bake for 35 to 40 minutes until the topping is golden brown and the cherry filling is bubbling around the edges.
09 - Allow bars to cool completely in the pan. Using the parchment overhang, lift the entire slab out and cut into individual bars before serving.