Cook caramel sauce: chop the candies and boil with cream until the candies are dissolved. Leave to cool, then chill. In the meantime, break the chocolate into pieces and melt in a hot water bath, let it cool down a little.
Preheat oven (electric cooker: 175 °C/circulating air: 150 °C/gas: see manufacturer). Grease a springform pan (26 cm Ø) and dust with flour.
Mix 125 g flour, cocoa and baking powder. Whip 125 g butter and sugar with the whisk of the mixer until creamy. Stir in the eggs. First stir in liquid chocolate, then flour mixture briefly.
Smooth the dough into the mould. Bake in a hot oven for about 20 minutes. Test with a chopstick. Take out, let rest in the form for about 10 minutes. Then remove from the tin and let it cool down completely.
Wash, halve and stone the peaches. Cut the flesh into slices, halve crosswise. Sprinkle with lemon juice and mix. For the cream mix mascarpone and "Fluff".
Cut the cake in half. Cover the bottom cake layer with half the cream, peaches and caramel sauce. Place the top layer, the rest of the cream, peaches and sauce on top.