I found this recipe in The Joy of Blueberries: Nature's Little Blue Powehouse by Theresa Millang. I love this book. It tells you how to grow blueberries, pick blueberries, and most of all, tons of recipes.
The recipe's tag is "A flavo[u]rful graham cracker-layered blueberry crisp." Well, I don't have graham cracker crumbs, but I had a bunch of Oreo baking crumbs. So I modified it. I also added blackberries to it. Both the blueberries and blackberries are farmer market fresh, so I was pretty stoked about it.
What you need:

Recipe (with adaptations)
2 cups Oreo Cookie baking crumbs (called for 1 cup graham cracker crumbs)
1/4 cup butter, melted
1 tablespoon granulated sugar
5 cups fresh blueberries and blackberries (mixed)
3/4 cup brown sugar, packed
1 teaspoon ground cinnamon
1 teaspoon ground nutmeg
1/8 teaspoon ground cloves (or roughly 4 shakes)
1/2 teaspoon salt (kosher salt)
1 teaspoon pure vanilla extract
2 tablespoons lemon juice
2 tablespoons water
First, mix in bowl first three ingredients. I found that 1 cup wasn't enough, so I added another cup.
Press 1/3 of the mixture into the bottom of a 2 quart baking dish. (I sprayed it with baking spray - 2 seconds, and then used a paper towel to spread it around.) Sprinkle 2 cups of mixed berries over the crumbs.
Mix brown sugar, spices and salt together, and stir in vanilla. Sprinkle 1/2 this mixture over the blueberries. Then sprinkle with 1 tablespoon of lemon juice and 1 tablespoon of water.
Repeat layers, with 1/3 crumb mixture, remaining berries, brown sugar mixture and lemon juice/water. Top with remaining crumbs.
Cover with tinfoil and bake 40 minutes in a 350 F oven. Increase temperature to 400 F and bake another 10 minutes.