Sour Cream-Orange Coffee Cake with Chocolate Streusel

Preheat oven to 350°F. Grease a 13x9x2-inch baking pan; set aside.

For topping, in a small bowl stir together brown sugar, the 1/2 cup flour, and the cocoa powder. Using a pastry blender, cut in the 1/4 cup cold butter until mixture resembles coarse crumbs. Stir in chocolate pieces and pecans; set aside.

In a medium bowl stir together the 3-3/4 cups flour, the baking powder, baking soda, and salt. Sprinkle orange peel over top of mixture; using fingers, distribute orange peel evenly through flour mixture. Set aside.

In a very large mixing bowl beat the 3/4 cup butter and the granulated sugar with an electric mixer on medium speed for 2 minutes. Add eggs, one at a time, beating well after each addition. Beat in sour cream, milk, orange juice, and vanilla until combined. Gradually beat in flour mixture on low speed. Beat for 2 minutes more or until smooth.

Spread half of the batter in the prepared pan. Sprinkle half of the topping evenly over the batter. Using the back of a spoon, press topping gently into the batter. Spread the remaining batter over topping. Sprinkle remaining topping over batter.

Bake for 50 to 55 minutes or until a wooden toothpick inserted near the center comes out clean. Cool in pan on a wire rack for 15 minutes. Serve warm or at room temperature.