Blueberry Crumb Cake

Charity

ingredients

Crumbs

5 tablespoons unsalted butter at room temperature
1/4 cup sugar
1/3 cup light brown sugar (packed)
1/3 cup all purpose flour
1/4 tsp salt
1/2 cup chopped walnuts

Cake

1 pint (2 cups) blueberries (preferably fresh, or frozen, not thawed)
2 cups plus 2 tsp all purpose flour
2 tsp baking powder
1/2 tsp baking soda
1/4 tsp salt
1/4 tsp ground cinnamon
1/8 tsp freshly ground nutmeg
2/3 cup sugar
grated zest of 1/2 lemon or 1/4 orange
3/4 stick (6 tbsp) unsalted butter at room temp
2 large eggs, at room temp
1 tsp vanilla extract
1/2 cup buttermilk

directions

1
Preheat oven to 350°F. Butter an 8-inch square pan and put it on a baking sheet.To make the crumbs: Put all the ingredients except the nuts in a food processor and pulse just until the mixture forms clumps and curds and holds together when pressed. Scrape the topping into a bowl, stir in the nuts and press a piece of plastic wrap against the surface. Refrigerate until needed. (Covered well the crumb mix can be refrigerated for up to 3 days.)
2
To make the cake: Using your fingertips, toss the blueberries and 2 tsp of the flour together in a small bowl just to coat the berries; set aside. Whisk together the remaining 2 cups flour, baking powder, baking soda, salt, cinnamon and nutmeg.
3
Working in the bowl of a stand mixer or in another large bowl, rub the sugar and zest together with your fingertips until the sugar is moist and aromatic. Add the butter and, with the paddle or whisk attachment, or with a hand mixer, beat the sugar with the butter at medium speed until light, about 3 minutes. Add the eggs one by one, beating for about 1 minute after each addition, then beat in the vanilla extract. Don’t be concerned if the batter looks curdled — it will soon smooth out. Reduce the mixer speed to low and add the flour mixture and the buttermilk alternately, the flour in 3 parts and the buttermilk in 2 (begin and end with the dry ingredients.) You will have a thick, creamy batter. With a rubber spatula, gently stir in the berries.
4
Scrape the batter into the buttered pan and smooth the top gently with the spatula. Pull the crumb mix from the fridge and, with your fingertips, break it into pieces. There’s no need to try to get even pieces — these are crumbs, they’re supposed to be lumpy and bumpy and every shape and size. Scatter the crumbs over the batter, pressing them down ever so slightly.
5
Bake for 55 to 65 minutes, or until the crumbs are golden and a thin knife inserted into the center of the cake comes out clean. Transfer the cake to a rack and cool just until it is warm or until it reaches room temperature.