When what you need is a quick chocolate fix, this cake will hit the spot. All you need is 3 tablespoons (44.4 ml) cocoa powder, 4 tablespoons sugar, 4 tablespoons flour, 3 tablespoons milk, and an egg.  For a fudgy, gooey, extra-chocolatey version of this cake, skip the milk and add just one tablespoon of flour, or leave it out entirely. It will come out with a richer consistency.     If you love the flavor of Nutella, add 3 tablespoons (44.4 ml) to the mix.     You could also add a tablespoon or two of peanut butter if you're so inclined.     Espresso or brewed coffee add depth of flavor - throw in a teaspoon or two. Add a few shakes of cinnamon and cayenne pepper for a spicy variation. Any microwave-safe mug will do; just make sure the batter doesn't rise higher than 2/3 way to the rim. Grease the mug with butter or oil, then use a spoon to mix the batter thoroughly until all lumps are removed and the ingredients are completely incorporated.  If you don't have a microwave-safe mug, you can use a bowl or another dish. If you're planning to serve the cake to someone else instead of eating it straight from the dish, consider using a dish with a more cake-like shape, such as a ramekin. Start by microwaving for 1 1/2 minutes. Check to make sure the mug isn't overflowing with batter; if it is, wipe it off and let it rest for a second. Then close the door and microwave for another 1 1/2 minutes before removing the mug from the microwave. If you wish, add some toppings like icing, whipped cream, or strawberries before enjoying your cake.

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Write a summary of the previous text in Chinese:
备齐材料。 将材料放入预先涂上油的杯子里混合一起。 将面糊放入微波炉高温加热。 你可把蛋糕转放在碟子上，或直接就着杯子吃蛋糕。