My instapot has a bunch of functions including crockpot...and steam, which is great for reheating leftovers. (We do not own a microwave.)
I don’t own a microwave either. Here’s my trick...When I have leftovers, I put the pan of whatever right in the fridge. It makes you eat the leftovers cuz having a pan take up the room in the fridge is just not right. Living alone has advantages. I also gulp milk right out of the bottle. lol