semisweet chocolate chips, chopped
unsalted butter, softened
(8-ounce) container sour cream
- Heat oven to 350°F. Lightly coat a 12-cup Bundt pan with vegetable cooking spray.
- In a small bowl, combine the chocolate chips, walnuts, 1/2 teaspoon cinnamon, and 1/4 cup sugar. Set aside.
- In a large bowl, with an electric mixer at medium-high speed, beat the butter with the remaining sugar until light and fluffy. Reduce speed to slow, add the rest of the cinnamon and the remaining ingredients, and beat 3 minutes or just until smooth.
- Sprinkle a third of the chocolate-nut sugar on the inside of the pan. Drop in half the batter in big spoonfuls. Sprinkle with another third of the chocolate-nut sugar mixture and top with the remaining batter. Sprinkle with the remaining chocolate-nut sugar.
- Bake 40 to 45 minutes or until a toothpick inserted in the center comes out clean. Cool in pan on a wire rack. Turn the coffee cake out of the pan and cool completely before cutting. Serve crusty side up.