Sour Cream Blackberry Bars

• 分量: One 9”x9” pan

材料

For the crust and topping:

125g all purpose flour

65g spelt flour

60g oat flour

50g granulated sugar

50g light brown sugar

4g (1 tsp) kosher salt (Diamond Crystal)

1/4 tsp baking soda

20g poppy seeds

170g unsalted butter, cold and cubed

30g full-fat sour cream

1/2 tsp vanilla

30g rolled oats

Coarse sugar, for sprinkling

For the filling:

200g full-fat sour cream

65g granulated sugar

1 large egg

2 tsp freshly squeezed lemon juice

8g (1 Tbsp) all-purpose flour

2g (1/2 tsp) kosher salt (Diamond Crystal)

1 tsp vanilla extract

340g fresh blackberries, halved if large

手順

Preheat the oven to 350°F with a rack in the middle. Line a 9 x 9-inch pan with two long criss-crossed pieces of parchment, leaving a couple of inches of overhang on all sides — secure with metal bulldog clips if desired. (This will make it easy to remove the bars later.) Lightly grease the parchment.

In the bowl of a food processor, combine the flours, sugars, salt, baking soda, and poppy seeds. Pulse to combine. Scatter the cold, cubed butter over the top. Process in short pulses until no large pieces of butter remain and the mixture resembles coarse cornmeal. Add the sour cream and vanilla and pulse until the mixture starts clumping together.

Transfer about a third (~190g) of the mixture to a separate bowl. Add the rolled oats and use your fingertips to pinch in, forming a clumpy streusel. Refrigerate until needed.

Transfer the remaining two-thirds of the mixture to the prepared pan. Use your fingers or the bottom of a small glass or measuring cup to press the crumbs evenly into the bottom of the pan. Prick all over with a fork. Bake for about 15-20 minutes, or until set. Transfer to a wire rack while you prepare the filling (no need to let it cool completely).

To make the filling, whisk together all filling ingredients except blackberries until smooth. Fold in the blackberries. Pour filling over par-baked crust and spread out evenly, then top with the reserved streusel mixture. Sprinkle generously with coarse sugar.

Bake until the crumb topping and custard are set (a toothpick inserted into the center should come out clean), about 30 minutes. Cool completely on a wire rack, then chill for at least an hour in the refrigerator before slicing. Refrigerate leftover bars in an airtight container for up to 5 days; serve cold or at cool room temperature.