Line a 18-20 cm (7-8 inch) cake pan with a circle of baking paper. Grease well the pan on top of the paper.
In a bowl combine flour and baking powder and whisk.
In a heatproof bowl combine cocoa powder, sugar and butter. Place the bowl in a pan of gently simmering water and mix until the butter is almost melted and all ingredients are combined. Transfer the mixture into a mixing bowl and whisk energetically until the remaining butter pieces melt completely.
Add the egg (make sure it is at room temperature) and whisk until homogeneous. Carefully fold in the flour mixture.
Transfer the brownie batter into the prepared pan. Bake for about 15 minutes or until a toothpick inserted in the centre comes out clean.
Let the brownie cool on a wire rack until room temperature.
Ice cream layers:
In a large mixing bowl beat together cream cheese, condensed milk and vanilla until smooth.
In another large bowl whip the cold cream until very thick.
Using a rubber spatula fold the whipped cream into the condensed milk mixture.
When the two mixtures are combined, divide the resulting ice cream base in two equal parts (simply transfer half of it into the bowl where the cream was whipped). Add the chopped cherries into one half and stir gently until they are evenly distributed.
Place the brownie base on a serving plate and put a cake ring around it. Alternatively place the base in the spring form pan where it has been baked.
Spoon the cherry vanilla ice cream mixture on top and smooth it with a spatula. Place the pan/ the plate in the freezer while preparing the chocolate mixture.
Melt the chocolate combined with the sea salt over a pan of gently simmering water. Using a rubber spatula carefully fold the chocolate into the second half of the vanilla ice cream mixture. Mix gently until uniform. Spoon the chocolate ice cream on top of the vanilla-cherry layer. Smooth with a spatula and cover with a cling film.
Freeze for at least 8 hours or overnight.
Melt the chocolate together with the milk over a pan of simmering water. Mix well, until homogeneous. Let the glaze sit for 5-10 minutes, until reaching room temperature.
Take the frozen cake out of the freezer. In about 5 minutes remove the cake ring.
Spoon the glaze on top of the cake and smooth it out.
Decorate the cake with fresh cherries.
Keep leftovers in the freezer, covered well with cling film. Before cutting and serving always let the cake stay at room temperature for 10-15 minutes.
Refrigerate the cream for at least 6-8 hours on the top rack of the fridge, before whipping it.