You will need:
A single crust pastry case of your own making (or shop bought if you really must) that has been partially pre-baked and cooled.
2 large eggs, room temperature
2 cups full fat sour cream, room temperature
3/4 cup granulated sugar
1/3 cup all-purpose flour
1/2 teaspoon vanilla extract
1/2 teaspoon grated orange zest
Big pinch of salt
3 cups of fresh blackberries
3 Tablespoons all purpose flour
2 Tablespoons firmly packed light brown sugar
1 tablespoon butter
1. Heat the oven to 350F
2. Whisk the eggs in a large bowl until frothy. Add the sour cream, granulated sugar, flour, vanilla, orange zest and salt, stirring evenly until blended.
Here's everything ready to assemble!
3. Spread the berries evenly across the partially baked and cooled pie crust, then ladle the sour cream mixture over the top of the berries.
4. Make the streusel by combining the flour and brown sugar in a small bowl with your fingers. Add the butter, stirring with a fork. Switch to your fingers and gently rub the topping until it is crumbly. Sprinkle the topping evenly over the sour cream filling.
5.Place the pie on the center oven rack and bake until the filling is set, about 35 minutes. When done the filling will have puffed slightly and will no longer seem liquid/loose. The pie doesn't brown heavily as it is not in the oven long.
6. Transfer the pie to a wire rack and allow to cool thoroughly. Serve at room temperature and refrigerate any leftovers :)