An 8-inch square pan (pretty common for quick coffee cakes) holds about 8 cups of batter, so any recipe sized for that pan will make 8 mug cakes. Think of this as making your own cake mix for a coffee ...

This deliciously moist, vanilla-scented cake features a cinnamon-brown sugar swirl in the middle and buttery streusel on top. As it bakes, the batter puffs up and creates delectably sweet, ...