Do you love sandwiches with fried onions on top but you don't want to actually fry onions? I figured out a trick that will save you the time and the grease. Microwave the onions.
Just cut up the onions and put them on a paper towel and nuke them in the microwave for 90 seconds. Then remove the towel and let them cool. Get two slices of bread - put half the onions on one slice - add a layer of cheese - the roast beef - another layer of cheese - the rest of the onions - and cap it with the other slice of bread. Then pop the sandwich into the microwave and nuke it for about 45 seconds and melt the cheese in good. Let it cool for about a minute and you have a great sandwich.
Technically the onions aren't fried - they are boiled but without being boiled in water. The onion tase is preserved but the raw onion taste is gone. They have the same taste as fried onions but are more consistent and don't have the drippy fluids that you get with frying. It's a healthier sandwich with a better taste.