Brown sugar, lightly packed
Heat oven to 350°F. Spray four nonstick bundt pans with nonstick cooking spray. Set aside.
Sift cake flour, baking powder and baking soda into a mixing bowl; set aside. Cream butter in a 12-quart mixing bowl, using a paddle attachment. Add Splenda® Granulated and eggs. Beat until smooth. Add the egg substitute and vanilla. Beat briefly to incorporate. Add applesauce and half of the sour cream. Add reserved sifted ingredients. Beat until smooth. Add remaining sour cream and blend just until incorporated and batter is uniform. Set aside.
Place 1/4 of cake batter in a bowl. Add brown sugar and cinnamon. Stir well.
Place 1/8 of the cake batter into each prepared pan. Place 1/4 of filling into each pan. Swirl with knife. Cover filling in each pan with 1/4 of the remaining batter.
Bake 50–60 minutes or until a toothpick inserted near the center comes out clean.