Buttering and flouring a pan. You do this so that whatever you put in the pan doesn’t stick to it (because no matter what they say, stuff always sticks to Teflon). You don’t want to use non-stick sprays because while they’re super-convenient they can also eat away at the coating of the pan and it’s gross.
All you do is coat the pan with butter and then pour some flour in it. You roll the pan around until the flour sticks to all the butter and coats the pan. This works really well to keep the cake from sticking to the pan, and the worst that can happen is that your cake or whatever has a little flour at the bottom of it when it’s done. Ain’t no thing.