To make the coffeecake even faster to prepare in the morning, prepare the streusel and measure out the dry ingredients for the cake the night before.
Serves 8
Streusel
1/3 cup packed light brown sugar
1/3 cup granulated sugar
1 tablespoon ground cnnamon
1 tablespoon unsalted butter, melted and cooled
1 cup pecans, almonds, or walnuts, chopped coarse
Cake
3 cups unbleached all-purpose flour
1 tablespoon baking powder
1 teaspoon baking soda
1 teaspoon ground cinnamon
1/4 teaspoon table salt
1 3/4 cups buttermilk or whole plain yogurt
1 cup packed light brown sugar
1 cup granulated sugar
3 large eggs
7 tablespoons unsalted butter, melted and cooled
1. For the streusel: Mix sugars, cinnamon, and melted butter together in medium bowl until mixture resembles wet sand; stir in nuts and set aside.
2. For the cake: Adjust oven rack to middle position and heat oven to 350 degrees. Generously coat 13x9 inch baking pan with nonstick cooking spray.
3. Mix flour, baking powder, baking soda, cinnamon, and salt together in large bowl. Whisk buttermilk, sugars, eggs, and melted butter in separate bowl until smooth. Using rubber spatula, gently fold egg mixture into flour mixture and stir until batter looks smooth and well combined.
4. Using rubber spatula, scrape batter into prepared pan and smooth top. Sprinkle streusel evely over batter. Bake until streusel is golden and toothpick inserted into center comes out with just a few crumbs attached, 40 to 45 minutes. Cool cake on wire rack for 15 minutes before slicing and serving