Balsamic Red Onion and Gruyere Panini/Grilled Cheese

• 1 red onion, thinly sliced
• 1 tablespoon balsamic vinegar (or to taste)
• 12 tablespoon olive oil
• 1 pinch salt
• 1 teaspoon sugar
• 8 slices sourdough bread
• 4 ounces gruyere cheese, shredded
• white truffle oil (optional)

1. Place onions, balsamic, oil, salt and sugar in sauce pan, cover and cook on medium low until very soft.
2. The onions should still be purple in color (if they are black there is probably too much vinegar -- remember you can always add more but you can't take it out).
3. Put together cheese and onion on bread.
4. Spray with truffle oil and grill in pan or panini press.
5. Dunk it in tomato basil soup.
6. Yum.

red onion, balsamic vinegar, olive oil, salt, sugar, bread, gruyere cheese, truffle oil

Taken from www.food.com/recipe/balsamic-red-onion-and-gruyere-panini-grilled-cheese-268033 (may not work)