Would the frosting ingredient amount be enough to fill the center, a crumb coat and an outer layer of frosting? This cake is a showstopper that a baker with rudimentary expertise could pull off. The topping can be a toffee glaze made with brown sugar, agave, butter and sea salt; https://wordpress93714.ampedpages.com/the-smart-trick-of-toffee-cake-calories-that-no-one-is-discussing-55947827