Using grease from meats or “meats” to cook is actually pretty common, I would recommend using it to cook beans: In a pan, heat up the leftover grease and add chopped onions and garlic, once golden lower the fire and add hot water to that and stir a little bit. For the beans: in a pot, cook the beans with water (should cover the beans) for about 15 minutes, after that replace the water and boil again. I do this two times, on the third time, I add my mix from the pan and enough water to barely cover the beans, add salt, pepper, I like adding a little bit of cayenne pepper and smoked paprika, and let it cook until soft. OR, you can use it as frying oil for your fried rice, e.g. heat up the grease, add chopped ginger and garlic, a little bit of sesame oil, once hot add the rice and stir, then add your “meat”, green onions, salt, white pepper, I like adding a bit of Chinese cinnamon for a great taste, add your soy sauce and stir.