Step #2 Coat bottoms of two 8" round cake pans with cooking spray (avoid sides).
Step #3 Line bottoms with waxed paper & coat paper with cooking spray.
Step #4 Set aside.
Step #5 2.
Step #6 Beat sugar & butter at medium speed of mixer until well-mixed.
Step #7 slowly add egg substitute & beat well.
Step #8 3.
Step #9 mix flour, baking soda & salt in bowl.
Step #10 With mixer on low, add flour mixture to sugar mixture alternately with sour cream, beginning & ending with flour mixture.
Step #11 carefully stir in the boiling water and vanilla.
Step #12 4.
Step #13 Pour batter into prepared pans.
Step #14 bake this at 350F for 35 mins or until cake springs back when touched in centre.
Step #15 Loosen layers from sides of pans & turn out onto wire racks.
Step #16 Peel off waxed paper & let cool.
Step #17 Frost layers & put together when completely cool.
Step #18 My notes: I frosted with "Chocolate Cream Cheese Frosting" because the frosting recipe printed with this cake can't be made ahead of time or it hardens.
Step #19 This is quite fudgy & rich.
Step #20 Not light & fluffy like cake-mix cake, if that's what you're looking for, but it was wonderful with the sweet icing & ice cream.