Coffee Mug Cake - cooking recipe

Ingredients

1 tablespoon butter, softened
2 tablespoons white sugar
1/2 beaten egg
2 tablespoons sour cream
2 drops vanilla extract, or more to taste
1/4 cup all-purpose flour
1/8 teaspoon baking powder
2 tablespoons all-purpose flour
1 tablespoon brown sugar
1 teaspoon cinnamon
1 tablespoon butter

Preparation

Stir 1 tablespoon softened butter and white sugar together in a coffee mug until fluffy; stir egg, sour cream, and vanilla extract into the butter mixture. Add 1/4 cup flour and baking powder into the mixture; stir until smooth.
Mix 2 tablespoons flour, brown sugar, and cinnamon together in a bowl. Mash 1 tablespoon butter into the flour mixture with a fork or pastry cutter until mixture is crumbly; sprinkle over the cake batter in the mug.
Cook in microwave oven on high for 1 minute. Continue cooking in 10-second intervals until a toothpick inserted into the middle comes out clean.