Crush the cinnamon flakes roughly. Mix 60 g cinnamon flakes, flour, baking soda, 1 pinch of salt, vanillin sugar and 100 g sugar. Mix oil, eggs and 250 g sour cream. Peel apples and grate them coarsely around the core, add them to the egg-oil mixture and quickly stir into the flour mixture.
There should still be small lumps of flour.
Place paper baking cups in the recesses of a muffin tray (12 recesses each). Spread the dough evenly into the baking cups. In a preheated oven (electric cooker: 175 °C/ circulating air: 150 °C/ gas: see
manufacturer) bake for about 12 minutes. Remove from the oven and let it cool down on a cake rack for about 1 hour.
Whip 150 g sour cream and 75 g sugar with the whisk of the hand mixer until creamy. Decorate muffins with sour cream. Sprinkle the rest of the cinnamon flakes on top.