Preheat the oven to 350 degrees F.
Spray a 9x13 inch pan with non-stick cooking spray.
Pour in the blueberry and strawberry pie filling into the baking pan.
Add in the vanilla and stir it thoroughly.
Sprinkle cake mix on top of the berries. Make sure to cover the berries entirely and don’t let any shine through.
Drizzle melted unsalted butter on top of cake.
Add pecans to the top of the cake mix.
Combine cinnamon and sugar in a small bowl and mix well. Sprinkle on top of cake.
Bake 45-50 minutes or until the top is golden brown and some of the berries are boiling out the top.