Mix the rum and lemon juice, pour over the cherries and leave covered until further use.
Beat eggs with sugar and cinnamon until frothy. Add the flour, baking powder and melted butter and stir. Now fold the cherries (including the rum-lemon juice) and the cornflakes into the batter. Put the mixture in a buttered casserole dish. Bake at 180 ° C for approx. 35 - 60 minutes (varies a lot depending on the oven, whether conventional or hot air). Let cool down a little and serve with fresh vanilla sauce while still warm.