1.Preheat the oven to 350°F. Spray two 9-inch round cake pans with vegetable spray and lightly dust with flour.
2. Pour boiling water over the oats, cover and let stand 20 minutes.
3. Meanwhile, combine the flour, sugars, baking soda, salt, cinnamon, and nutmeg in a large mixing bowl.
4. Combine the applesauce, 2 egg whites and vanilla in a small bowl and blend well.
5. Add the applesauce mixture and oatmeal to the dry ingredients and mix well with a fork until blended.
6. Spoon the batter into the cake pans and bake for 25-30 minutes, or until cake tester inserted into center of cakes comes out clean.
7. Cover the top of the cakes with waxed paper, invert and cool on cake racks.
To make meringue:
1. Boil the maple syrup to "firm-ball" stage (248 degrees on your candy thermometer).
2. Beat 3 egg whites until they form stiff peaks but are not dry.
3. Gradually add the hot maple syrup to beaten egg whites and beat until fluffy.
Put it all together:
1. Set the first cake layer on a 9-inch cardboard round or cake plate.
2. Place 3-inch strips of waxed paper under edges of cake (this will prevent any frosting from getting on the plate).
3. Spread a thick layer of meringue on the first layer .
4. Place the second layer on top and frost the top and sides of the cake with the remaining meringue.
5. Remove and discard waxed paper strips.