Transfer the butter to a saucepan and start heating it.

Once it has completely melted, continue heating it for a moment until you see small brown specks in it. Then remove the saucepan from the stove and set the butter aside to cool.

Mix together the flour and baking powder.

Prepare a baking pan - line it with baking paper or grease it with butter and sprinkle with breadcrumbs or flour.

Preheat the oven to 180℃ (top/bottom heat mode) or 170℃ (fan-forced).

Beat the eggs together with sugar on high speed with a mixer until they are nicely fluffy - I beat for about 3 minutes.

Slowly add the cooled butter to the eggs and mix together on low speed.

Add about half of the flour with baking powder to the bowl and mix on low speed.

Add buttermilk and mix briefly

Add the rest of the flour and mix briefly - stop mixing when there are still traces of flour visible on the sides.

Then just mix the batter with a spoon.

Transfer the batter to the prepared pan.

Place the pan with the cake on the middle rack, or slightly below, and bake for about 30 minutes - until a dry skewer comes out clean.

After baking, set the cake aside to cool.

Mix the hot coffee with the condensed milk; once well combined, pour in the regular milk and stir.

Prick the cake in the pan densely with a skewer - e.g., a kebab skewer.

Pour the coffee fairly evenly over the top of the cake, lightly spreading it.

Transfer the mascarpone to a bowl, add condensed milk and dissolved coffee - mix until combined. If you prefer a sweeter cream, you can add more condensed milk.

Spread the cream over the cake and smooth it into an even layer.

Finally, you can additionally sprinkle the top of the cake with instant coffee powder or cocoa.