Cream 300 g butter, flour, cornstarch, salt, cinnamon and lemon zest with the whisk of the hand mixer. Gradually stir in 300 g sugar and eggs. Grease the fat pan of the oven (37cm x 32 cm), place the dough on top and smooth it down.
Roughly chop the cherries. Melt remaining butter in a pot, add remaining sugar and vanilla sugar and simmer for 2-3 minutes at low heat, stirring several times. Stir in oat flakes, peanuts and cherries.
Bake the dough in a preheated oven (electric: 175 °C/ gas: level 2) for about 30 minutes. After 10 minutes of baking time, carefully spread the oat flake nut mixture on the dough. Take the tray out of the oven and let it cool down.
Cut into diamonds with a sharp heavy knife. Chop the white and semi-sweet couverture and melt separately in two bowls in a hot water bath. Dip half of the lozenges into white couverture, the remaining lozenges into plain couverture and leave to dry.
Results in about 75 pieces.