Preheat Oven: Set your oven to 350°F.
Mix Dry Ingredients: In a large bowl, combine all-purpose flour, almond flour, 3/4 cup sugar, baking powder, kosher salt, and lemon zest.
Incorporate Butter: Add the room-temperature butter and mix until fully combined with the dry ingredients. You can use a spatula or your hands until no butter chunks remain.
Add Wet Ingredients: Mix in the egg, almond extract, and lemon juice. Stir until a soft, sticky dough forms, similar to cookie dough.
Prep Cherries: In a separate bowl, mix the pitted cherries with 3 tablespoons of sugar and 1 tablespoon of cornstarch. Set aside.
Prepare Pan: Line a 9x9-inch or 8x8-inch baking pan with parchment paper.
Layer Dough: Spread half the dough evenly in the bottom of the pan.
Add Cherries: Pour the cherry mixture over the dough, spreading it evenly.
Top with Dough: Drop spoonfuls of the remaining dough over the cherries, then use your hands to spread it out and flatten. If the dough is sticky, lightly flour your hands.
Bake: Bake for about 45 minutes, until the top is golden brown. It might take up to an hour depending on your pan and oven.
Cool: Allow the bars to cool completely before slicing.