Spiced Sweet Potato Pound Cake with Caramel Frosting

For the Sweet Potato Pound Cake:

unsalted butter (softened)

granulated sugar

large eggs (at room temperature)

buttermilk (or 3 Tablespoons whole milk mixed with 1/2 teaspoon of white vinegar)

all-purpose flour

salt

baking powder

baking soda

ground cinnamon

ground nutmeg

cooked (peeled, and cooled mashed sweet potatoes (or you can use canned golden cut sweet potatoes yams in syrup -- drain the syrup and mash the yams))

pure vanilla extract

For the Caramel Frosting:

dark brown sugar

unsalted butter

heavy whipping cream

pure vanilla extract

powdered sugar