1, vinegar+baking soda. Practice: soak the burnt casserole in water 1 hour, first clean the burnt part of the surface, then pour vinegar and baking soda powder, pour some water, put the casserole on the gas stove to boil hot water and soak it for half an hour, and finally scrub it with steel balls.

2, detergent+baking soda. Detergent can remove stains and oil stains, so detergent and baking soda can also effectively remove black stains from casserole. The method is to burn the surface clean first, then pour the detergent and baking soda into it and soak it in hot water for half an hour, and then brush it with a steel ball to make it shiny.

3, vinegar+salt. Vinegar and edible salt are also the best ways to remove stains. Pour some water into the burnt casserole, put it on the gas stove, soak it for half an hour after boiling, and then scrub it with steel balls. If there are still some stubborn black scorch marks at the bottom, add edible salt and vinegar and scrub with steel balls, and the oil stain will be washed away soon.