Line 2 (10-inch) (25 centimeters) cake tins with greaseproof paper and rub with a little butter. In a mixer, beat the butter and sugar together until fluffy. Add the eggs, flour, baking powder, and cocoa powder. Mix well and divide into the cake tins. Cook for 7 to 8 minutes at 350 degrees F (180 degrees C/gas 4) until firm but soft.
So, you have 7 to 8 minutes, while the sponge is cooking, to make the filling. Add the ricotta to a food processor and blitz with the sugar until shiny and smooth. Scoop into a bowl, add the chopped fruit, cherries, chocolate, and almonds and stir together. Now add the coffee to taste (bash the hell out of the beans using something heavy wrapped in a tea towel, or use a coffee grinder if you don't like too much noise?). Whip up the egg whites and fold into the ricotta mix.
By now, the sponge is probably ready. Turn it out while it is still hot and cut it into 8 wedges. Line a shallow round bowl, about 9-inches (23 centimeters) across, with two sheets of cling film, making sure it fits the shape of the bowl. Then fit half of the sponge pieces neatly around the insides of the bowl (as you would if you were making summer pudding).
Drizzle with liqueur, then pour in the ricotta mixture. Level it out, then place the remaining sponge over the top. Drizzle again with liqueur. Pull the cling film over the top and weigh it down with some plates, pushing down on them before placing in the freezer for at least 4 hours. Serve this 'semi freddo' (semi frozen), dusted with cocoa powder and sliced into wedges. If it's very frozen then that's fine; just pull it out of the fridge when dinner is served so it can slowly thaw as you are eating.