Preheat oven to 375°F (190°C). Grease a 9″ square baking dish (or 10" round baking dish), set aside.

In a medium bowl, combine flour, granola, and sugar. Add melted butter, stir until well incorporated. Everything should be wet, but crumbly.

Peel (if you want – I don’t usually), core, and chop or slice the apples, placing in a large mixing bowl.

Toss the sliced apples with the sugar, lemon juice, zest, corn starch, vanilla, cinnamon, and salt.

Add blackberries, toss until the fruit is evenly coated.

Spread apple mixture evenly over the bottom of the prepared baking dish.

Top with an even layer of the granola mixture, patting down lightly.

Bake for 35-40 minutes, or until topping is lightly browned, and apples are tender.

Serve with a scoop of ice cream or mound of whipped cream.

Leftovers can be stored in an airtight container in the fridge for a week or so.

For best results, don't cover it til after it's cooled to room temperature!