Select a small mug to make your cookie in. It should have room to expand as it bakes, so use a mug that holds about 8 ounces. Place 1 tablespoon of butter in the mug and microwave it until it melts. It will only take a little time in the microwave for the butter to melt. Try 5 seconds before adding more time. You don't want to boil the butter or it will start sputtering in your microwave. Stir in 1 tablespoon of granulated sugar, 1 tablespoon of packed brown sugar, and one pinch of salt. You can use a spoon, a fork or a small spatula to stir. Ensure that the mixture is completely combined and that there are no lumps of brown sugar. You can use 2 tablespoons of just one kind of sugar, if you like. The brown sugar will give a richer flavor because it's flavored with molasses. Crack 1 egg and separate the yellow yolk from the egg white. Throw away the egg white since you won't need it for this recipe. Add the egg yolk to the mug with your creamed butter and sugar mixture. Stir in the egg yolk until it's completely combined. You could store the egg white in the refrigerator to use in another recipe. Just use it within a few days. Add a little less than 1/4 cup of flour and stir it into the mug just until you can't see the flour anymore. Add 2 full tablespoons of chocolate chips and stir it again so the chocolate chips are evenly distributed in the mug. Avoid eating any of this cookie dough before cooking it since it does contain raw egg yolk. Place the mug of cookie dough in the microwave and cook it for 40 seconds. Check to see if the cookie is done. If it is, the cookie will look dry. If it looks runny or raw, microwave the cookie in 10 second intervals until it looks cooked. Serve or eat the cookie immediately. Avoid microwaving the cookie for more than 1 minute total. The cookie will keep cooking as it cools, so you don't want to microwave it too much.

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Write a summary of the previous text in Chinese:
融化黄油。 加糖、香草和盐。 加蛋黄。 加面粉和巧克力豆。 用微波炉烤杯装曲奇。