I come from an Ice cream manufacturing family - we always took the easy way out to save time - a bought sponge, ice cream, and a made meringue
Use a block of solid ice cream not the easiserve type as it melts too quickly.
Place sponge on a baking tray, place block of ice cream on top, we put jam on top too, then surround the whole thing with meringue, making sure there are no gaps at all. Heat up oven to 230 degrees c, place in oven for 3 to 4 minutes.
It is the easiest pud ever to make and so so impressive! all it needs is a wee bit of faith!

It really does work!