Malted milk coffee cake

Bring the butter, eggs and buttermilk to room temperature.

Put a quarter of the softened butter in a bowl for the streusel.

Add brown sugar, flour, malted milk powder and kosher salt and rub together with fingertips to a heterogeneous mixture with big clumps.

Grease a nine inch square pan with butter.

Cream the remaining butter with 200 grams of sugar until really fluffy.

Beat in the eggs one at a time until smooth and fluffy.

Whip in the buttermilk and about a tablespoon of vanilla; the mixture may look gritty at this stage.

Add the malted milk powder, baking powder, baking soda if used, and kosher salt.

Mix in a little of the all-purpose flour until smooth, then the rest gradually, to about 270 grams, adjusting by look — a little wetter than cookie dough.

Mix a whole tablespoon of cinnamon into the streusel; it does not need to be homogenous.

Variation: put in half the batter, sprinkle a layer of brown sugar with cocoa or cinnamon for a ribbon, then the rest of the batter.

Smooth the batter and sprinkle the streusel over, squeezing some into big chunks.

Bake at 350 Fahrenheit, 180 Celsius, for 45 minutes and up to just under an hour, until a skewer to the centre comes out clean. Drop 10 to 15 degrees on convection so the topping does not burn.

Cool all the way before cutting. The streusel is hard and crunchy fresh baked and softens by the next day.