Pecan Filling

1. Preheat oven to 325F/163C and heavily grease a 1lb loaf pan, set aside while you prepare the filling.
2. In a small saucepan, add the brown sugar, butter, and chopped pecans. Cook for 5-7 minutes over low-medium heat to toast the pecans in the melted butter and sugar. Set aside to cool while you prepare the cake.

Cake

1. In the bowl of an electric stand mixer fitted with a paddle attachment or a large mixing bowl with a handheld electric mixer, beat the butter and sugars, and mix on low-medium speed for 3-4 minutes. Once the mixture is light and fluffy, make sure to scrape down the side of the bowl so everything is fully combined, then add the eggs one at a time.
2. In a small bowl, whisk together the flour, baking powder, and salt. Then, in a separate bowl, mix together the vanilla extract and sour cream.
3. Add 1/3 of the flour mixture to the butter mixture and mix to combine, then add 1/2 of the sour cream mixture, mix to combine, then 1/3 of the dry ingredients and repeat with the remaining sour cream and dry ingredients, mixing until just combined. Add the caramelized pecans with the last bit of dry ingredients. You don't want to overmix the batter.
4. Pour into the prepared cake pan and use an offset spatula to spread the batter into an even layer. Bake for 55-65 minutes, the internal temperature of the cake should be 210F/99C. Let the cake cool in the pan for 20 minutes, then flip onto a wire rack to cool completely.

Glaze

1. In a bowl, whisk together the powdered sugar, milk, and vanilla extract. Pour on top of the cooled cake and spread into an even layer, then top with chopped pecans. Store leftovers in an air-tight container on the counter for up to 4 days.