Cinnamon Apple Cake

Core and peel the apples, slice into wedges, drizzle with lemon juice, and toss with sugar and cinnamon.

Combine the melted butter with sugar and vanilla sugar, mixing well. Beat in the eggs one at a time, then stir in room-temperature kefir.

In a separate bowl, whisk together the flour, baking powder, and salt. Fold the dry ingredients into the butter-egg mixture until a medium-thick batter forms.

Grease your baking pan or line it with parchment paper. Mix together the sugar and cinnamon for the topping.

Spread 1/3 of the batter into the pan, sprinkle with some of the topping, and add half of the apples. Repeat the layers: batter, topping, apples, topping.