Preheat oven to 375-degrees.
In a large bowl with a hand mixer or stand mixer, cream together the softened butter and sugar. Add the vanilla and eggs and beat well.
Add the flour, baking powder, cinnamon and salt to the butter mixture and blend until thoroughly combined.
Spread the dough evenly into the bottom of a 9 x 11 baking dish that has been sprayed liberally with baking spray.
Spread the canned peaches evenly over the crust layer in the baking dish. Top the canned peached with the fresh slices of peaches or nectarines and top with the blueberries. Set aside.
In a medium bowl, mix together all the crisp ingredients to form a crumbly, sandy mixture.
Sprinkle the crisp topping evenly over top of the fruit filling.
Bake in a preheated oven for 40 minutes, or until the crisp topping is golden brown and the fruit filling is starting to bubble up along the sides.
Cool slightly and serve warm.