Caramelized Onion Grilled Cheese Sandwich

• 3 tablespoons butter or 3 tablespoons margarine, softened
• 1 medium sweet onion, sliced and separated into rings
• 1 teaspoon brown sugar
• 8 slices pumpernickel bread
• 2 tablespoons stone ground mustard
• 8 slices muenster cheese

1. Over medium-high, melt 1 tablespoon of butter in a 12-inch nonstick skillet.
2. Add the onion; cook stirring for 3-5 minutes, until tender.
3. Reduce to medium-low heat, adding in the brown sugar.
4. Cook until onion is glazed and golden, around 20-25 minutes, stirring occasionally.
5. While cooking, spread mustard over 4 slices of bread; place cheese slice on each piece of bread.
6. Spoon the onion mixture evenly over cheese and other bread slices.
7. Spread tops of sandwiches with 1 tablespoon of butter.
8. In skillet, over medium-low, heat until hot, placing buttered side down.
9. Spread remaining butter on other sides and cook until cheese has melted.
10. Serve warm.

butter, sweet onion, brown sugar, bread, stone ground mustard, muenster cheese

Taken from www.food.com/recipe/caramelized-onion-grilled-cheese-sandwich-36236 (may not work)