Preheat the oven to 350F. Line a 9x13 baking pan with parchment paper, or grease (you choose)
Crust and Topping
In a food processor, pulse together the flour, sugar and salt.
Add the butter and pulse until the butter is crumbly (about a minute)
Reserve 1 1/2 Cups of the crust mixture (this is the topping)
Press the remaining mixture into the baking pan (distribute evenly)
Bake for 15 minutes - the edges should be JUST starting to brown.
Cool.
Filling
Whisk the eggs together in a bowl, and add the sugar, sour cream, flour, salt, zest and vanilla.
Add the blackberries and gently fold in.
Pour the mixture over the crust, then sprinkle the crumble topping evenly over the top.
Bake for 45-50 minutes (until center is not jiggly).
Cool completely before cutting into bars.
Devour.
Notes
If you don't have a food processor, no problem. You can cut the butter into the flour using two forks, or grab an inexpensive pastry blender tool.How to storeStore Blackberry Pie Bars covered on the counter for a few days. Hide them from your family.Substitutions/AdditionsAny kind of berry does great in this recipe. Try blueberries and raspberries!If using frozen berries, make sure to thaw and drain before using.