Preheat your oven to 350°F (175°C) and grease a 10-inch tube pan.

Cream together 1 cup of softened butter and 2 cups of granulated sugar.

Incorporate 4 large eggs one at a time, then mix in 2 teaspoons of vanilla extract.

In a separate bowl, whisk together 3 cups of all-purpose flour, 1 teaspoon of baking soda, and 1 teaspoon of salt.

Gradually add the dry mixture to the wet ingredients, alternating with 2 cups of sour cream.

Spoon one-third of the batter into the prepared pan.

Mix 1 cup of granulated sugar, 2 tablespoons of ground cinnamon, and 1/2 cup of chopped walnuts.

Sprinkle one-third of the topping over the batter in the pan.

Continue layering with remaining batter and topping until completed.

Bake for 60 to 65 minutes until a toothpick comes out clean.

Let the cake cool in the pan for 15 minutes, then transfer to a wire rack.