Preheat your oven to 350°F (175°C) and prepare three 9-inch cake pans by lining with parchment paper, then buttering and flouring them.

In a skillet over medium-low heat, melt some unsalted butter and add chopped pecans mixed with light brown sugar. Stir frequently for about 3-4 minutes until fragrant and golden, then cool.

In a medium bowl, combine buttermilk and milk; in another bowl, combine flour, baking powder, baking soda, and salt.

In a large bowl, beat softened butter and granulated sugar together until light and fluffy, about 4-5 minutes. Add vanilla, then eggs one at a time, mixing well.

Gradually add the flour mixture to the creamed butter mixture, alternating with the milk mixture, beginning and ending with the flour, mixing until just combined. Fold in the toasted pecans.

Divide the batter among the prepared cake pans and bake for 25-28 minutes or until a toothpick comes out clean. Cool in pans for about 15 minutes, then transfer to a wire rack.

To make the frosting, beat together cream cheese and unsalted butter until smooth, then gradually add sifted powdered sugar and vanilla, mixing until fluffy.

Once cooled, level each cake layer and spread cream cheese frosting between the layers, and frost the top and sides. Garnish with additional toasted pecans.