Crispy toppings on casseroles

When I make a casserole, I like to top it with something crispy, like French fried onions or tortilla chips. This works fine, right out of the oven. But of course, the purpose of making a casserole is to have leftovers, and I find that microwaving destroys any crispiness that might have been present originally. Is there any simple way around this?

For what it’s worth, I’m mostly eating the leftovers for lunch, and microwaves are the only heating implements available up at the office. So popping it back into the oven isn’t an option.

I usually just save some of the original crunchies like chips, french fried onions or ramen noodles and sprinkle them back on after I’ve reheated it. I’m a big fan of chips which are usually easy to obtain. A thing of soup and a 99cent vending machine bag of doritos satisfies my crunch craving.

Buttered breadcrumbs, even reheated, it always yum. It has to be REAL butter, though. It’s the butter that makes the lack of crunch forgivable.
~VOW

1 1/2 c Panko bread crumbs
4 tbs butter
1/4 tsp salt
Paprika

Melt the butter in a skillet then add the panko and sautee until the panko starts to brown. Add salt, and paprika for coloring.

Nummy num num.

I think he gets the concept of making crunchy things to put on top of casseroles. I believe, unless I am mistaken, that he would like to learn a method that requires just a casserole and a microwave so that he can create more crunchy topping at work.