Adapted from Food and Wine Magazine
3 tbsp unsalted butter, softened
1 tbsp olive oil
4 cups yellow or sweet onion, halved and thinly sliced crosswise
salt and freshly ground pepper
8 half-inch thick sliced of whole grain or sourdough bread
2 tbsp Dijon mustard
2 tbsp grainy mustard
1 cup smoked gryuere cheese, grated
1 cup sharp cheddar cheese, grated
4-6 pickles, thinly sliced lengthwise (I use sour pickles)
1. In a deep skillet, melt butter and olive oil. Add the onion, cover and cook over high heat, stirring once of twice until softened, about 5 minutes. Turn heat to medium, stirring occasionally until onions are tender and carmalized, about 25 minutes. Add water to the skillet as necessary, a 1/4 cup at a time to prevent the onion from burning. Season with salt and pepper and set aside.
2. Mix Dijon and grainy mustard together and spread on bread. Top with sliced of pickles, carmalized onions and shredded cheeses.
3. Butter outside slices of bread and grill until cheese is melted, cut in half and serve.