Grease 4 (8-inch) cake pans and line with parchment paper. Preheat the oven to 350 degrees.
Cream the butter and sugar together in a mixer on medium-high speed and beat for 3 minutes or until light and fluffy. Beat the eggs in, one at a time, scraping down the sides of the bowl after each addition. Beat in the vanilla.
In another mixing bowl, combine the Schär Gluten Free Mix It Universal All-Purpose Flour Alternative with the baking powder.
Turn the mixer to low, add half the flour mixture to the butter/egg mixture, then the milk, and finally the rest of the flour mixture. Beat until fully combined. Using a rubber spatula, scrape the sides and bottom of the mixing bowl and make sure the batter is fully mixed. Divide the batter evenly among the 4 prepared cake pans. Bake for 25-30 minutes or until a toothpick inserted into the center comes out clean. Let cool in pans for 10 minutes then transfer to a wire rack to finish cooling.
If the cakes are domed, slice off the dome so you have flat layers. Place one layer on a cake stand, spread on about ¼ cup of apricot preserves, top with another layer of cake and repeat, ending with a cake layer with no jam on it.
Frost the cake generously with chocolate frosting. Surround the cake with Twin Bars, pressing firmly into the frosting. If desired, tie a ribbon or burlap around the middle and decorate with edible fall leaves.