preformed baked goods filling

ok, we all know that you can inject creams and pudding into a cake or brownie to fill them, but what if you could buy a frozen ring of custard or jello or cream with 4 little "legs" about half an inch long that would support the ring? so imagine you are baking a bundt cake and you pour some batter in the ring, drop in the cream ring thats frozen to be solid, then pour more batter then bake, the ring will slowly melt while the cake bakes around it and when all is warm and baked (like the idea i hope) you have a perfectly placed ring of cream or whatever. alternately, sell a ring mold for making your own rings at home in the freezer.