Brown the butter: Melt 1 cup of unsalted butter over medium heat for about 5 minutes until golden brown.

Mix the base: In a bowl, combine cooled brown butter and 1 cup of sugar. Add 3 eggs one at a time, mixing well. Stir in 1 tablespoon of vanilla extract.

Combine dry ingredients: Sift together 2 cups of cake flour, 1 teaspoon of baking powder, and ½ teaspoon of salt. Fold into the wet ingredients.

Add cream and milk: Stir in ½ cup of sour cream and ¼ cup of whole milk until smooth.

Prepare to bake: Preheat oven to 350°F (175°C). Grease and flour a 9-inch round cake pan. Pour batter and sprinkle with 1 tablespoon of sugar.

Bake: Place the cake in the oven and bake for 35-40 minutes until golden brown and a toothpick comes out with a few moist crumbs.

Cool and serve: Let the cake cool in the pan for 10 minutes, then turn it out to cool completely. Serve plain or with fresh berries.