Place ring tin on cake base. Line sides with thinly sliced strawberries. Place a layer of sponge on base. Add half of mousse, using a spatula and a turntable squeeze the mousse into the cracks between the strawberries. Place another layer of sponge, pressing it flat. Pipe mousse into the cracks between the sponge and strawbs and tin sides, then flatten top with spatula and turntable. Freeze and unmold with blowtorch.