Coffee Cake

Preheat the oven to 175°C and grease the baking tin lightly with butter or line it with parchment paper.

Press the parchment into the corners so the tender cake can be lifted out without breaking after baking.

Rub part of the cold butter, part of the flour, part of the sugar, and 2 tsp ground cinnamon together with your fingertips.

Stop while the mixture still has coarse clumps, not a smooth paste, so it bakes into a crumbly streusel.

Beat the remaining softened butter and sugar with a whisk for about 2 minutes, until lighter in color and fluffy.

Add the 2 eggs one at a time, mixing well after each addition so the batter does not split.

Mix in 120 ml sour cream until smooth, then sift in the remaining 200 g flour.

Fold gently with a spatula only until dry streaks disappear; overmixing makes the sour cream cake dense instead of tender.

Spread half of the batter evenly in the prepared tin and scatter over some streusel.

Spoon on the remaining batter, level it gently without dragging the middle layer, then sprinkle the rest of the streusel across the top.

Bake at 175°C for about 35 minutes, until the top is golden and a skewer inserted in the center comes out without wet batter.

Cool in the tin for 10 minutes, then slice while still warm for the strongest cinnamon aroma.