Drain the peaches well in a sieve and cut in half. Place the fat, sugar, vanilla sugar, lemon zest and salt in a mixing bowl and whisk until foamy.
Add the eggs one by one, alternating with the cornstarch and stir well. Mix flour, ground almonds and baking powder and finally stir in briefly. Pour the dough into a greased glass baking tray (approx. 31 x 41 cm) dusted with flour and smooth it down.
Spread peaches on top and sprinkle with almond slivers. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 40-45 minutes. In the meantime, mix icing sugar, lemon juice and 1 tablespoon of hot water to a smooth glaze.
Spread the finished cake immediately with the icing and let it cool on a cake rack. Serve with whipped cream and cinnamon.