Heat oven to 350°Make brown sugar filling and set aside.Beat sugar, butter, vanilla and eggs. Alternate adding sour cream and dry ingredients until all combined. If you're making a bundt cake, spread 1/3 of batter then sprinkle with brown sugar filling. Repeat twice. If making 2 loaves, spread about 1 1/2 cups of batter, then sprinkle with brown sugar filling and repeat once. Bake bundt cake about 1 hour, and loaf pans about 45-50 minutes or until toothpick tests clean. Cool 10 minutes and remove from pans to cool on a wire rack. Add vanilla glaze. This is delicious served warm but its perfect to cool, wrap and share with a neighbor!