Since discovering this recipe a couple months ago, I've made these for dinner at least half a dozen times. They are so simple, but SO GOOD!!! To make prep faster, buy your ground beef in large quantities (it's usually cheaper this way too), make up your patties, wrap them in saran wrap and freeze them in a large plastic bag. Then throw a couple frozen patties on your Foreman grill (or however you normally cook hamburgers) and dinner's ready in about 10 minutes! We especially love eating them with sweet potato fries.
2 hamburgers with buns, prepared as desired
2 slices of mozzarella cheese
1 medium sized onion
1 Tbs oil
1/2 teaspoon sugar
1/4 cup water
1 Tbs balsamic vinegar
1. Heat oil in small/medium sized skillet over medium heat.
2. Slice your onion into long strips (I try to do 8ths or smaller). Add to frying pan, toss in oil and sprinkle with sugar.
3. Saute in frying pan, stirring frequently, until onion is a nice dark brown.
4. When onion is finished cooking, remove from heat and carefully add 1/4 cup water and vinegar. Mix well.
5. Top burgers with mozzarella cheese. Depending on the thickness of your cheese, you might want to microwave it for 10-15 seconds so that cheese gets nice and melty. Then add your onions and you're all set!
Inspiration recipe found here.