Ina Garten's Blueberry Crumb Cake
For the streusel
1/4 cup granulated sugar
cup light brown sugar, lightly packed
1/8 teaspoon ground nutmeg
cups all-purpose flour
For the cake:
3/4 cup granulated sugar
2 extra-large eggs, at room temperature
1/2 teaspoon grated lemon zest
2/3 cup sour cream
1 1/4 cups all-purpose flour
1 teaspoon baking powder
1/4 teaspoon baking soda
1/2 teaspoon kosher salt
Confectioners' sugar for sprinkling
Cream the butter and sugar in the bowl of an electric mixer fitted with the paddle attachment on high speed for 4 to 5 minutes, until light.
With the mixer on low speed, add the flour mixture to the batter until just combined.
Spoon the batter into the prepared pan and spread it out with a knife. With your fingers.
Crumble the topping evenly over the batter.