Lemon Blueberry Muffin Cake

Lemon Blueberry Muffin Cake 1/2 cup unsalted butter, room temperature zest from 1 large lemon 1 cups sugar 1 egg 1 tsp vanilla 2 cups flour 2 tsp baking powder 1 tsp kosher salt 2 cups fresh blueberries 3/4 - 1 cup buttermilk 1 Tbsp sugar Preheat the oven to 350ºF. Cream butter with lemon zest and 1 cup of the sugar until light and fluffy. Add the egg and vanilla and beat until combined. Meanwhile, toss the blueberries with 1/4 cup of flour, then whisk together the remaining flour, baking powder and salt. Add the flour mixture to the batter a little at a time, alternating with the buttermilk. Fold in the blueberries. Spray a 9-inch square baking pan with non-stick spray. Spread batter into pan. Sprinkle batter with remaining tablespoon of sugar. Bake for 34-45 minutes. Check with a toothpick for doneness.