Instructions

• Preheat the oven to 350°F (175°C). Grease and flour a 10-inch tube pan or bundt pan; set the pan aside.
• In a small bowl, combine 3/4 cup of the white sugar, 2 tablespoons ground cinnamon, and 1/2 cup chopped walnuts; set this cinnamon-sugar mixture aside.
• In a large mixing bowl, beat 1 cup softened butter and 2 cups white sugar together until light and fluffy.
• Add the 4 eggs, one at a time, beating well after each addition. Stir in 2 teaspoons vanilla extract.
• In a separate bowl, whisk together 3 cups all-purpose flour, 2 teaspoons baking powder, 1 teaspoon baking soda, and 1 teaspoon salt.
• Add the dry ingredients to the butter mixture alternately with 2 cups sour cream: add one-third of the dry ingredients, mix just until combined; add half of the sour cream, mix just until combined; add another third of the dry ingredients, mix just until combined; add the remaining sour cream, mix just until combined; add the final third of the dry ingredients and mix until just combined. Do not overmix.
• Spoon one-third of the batter into the prepared pan and spread it evenly. Sprinkle one-third of the reserved cinnamon-sugar mixture over the batter.
• Repeat the layering two more times: spoon another third of the batter over the cinnamon-sugar, sprinkle another third of the cinnamon-sugar, then add the final third of the batter and top with the remaining third of the cinnamon-sugar.
• Place the pan on the middle oven rack and bake at 350°F for 60–70 minutes, or until a toothpick inserted near the center comes out clean.
• Remove the cake from the oven and cool in the pan on a wire rack for 10 minutes. After 10 minutes, invert the cake onto the wire rack to remove it from the pan and allow it to cool before slicing.