The first step is to prepare about 500 grams of big black beans and 100 grams of old rock sugar, plus a proper amount of vinegar. The second step is to clean up the big black beans we have prepared and soak them for more than four hours. If four hours is too long, we'd better soak for one night in advance, so that it won't be too long. After soaking the black beans, wash them again, add sugar and vinegar, and gradually marinate for three hours. Step 3: After the time is up, immediately put the big black beans into the pot and simmer slowly, gradually boil the water in the pot, stir with a frying spoon after boiling, and avoid sticking the big black beans until they are cooked, and then take them out. Step 4, directly fry the black beans in an air electric frying pan for 24min, and fire at 180 degrees. It's time, so the nutritious and delicious black sugar beans are ready. It is not only used to cook porridge, but also can be eaten directly as a snack, which is especially delicious and not greasy. Interested friends can try to do it at home.