INGREDIENTS
4 tbsp
butter
1 tsp
salt
2
large red onions, thinly sliced
2
large sweet onions, thinly sliced
1 48 fluid_ounce can
chicken broth
1 14 ounce can
beef broth
1/2 cup
red wine
1 tbsp
Worcestershire sauce
2
sprigs fresh parsley
1
sprig fresh thyme leaves
1
bay leaf
1 tbsp
balsamic vinegar
salt and freshly ground black pepper
4
thick slices French or Italian bread
8
slices Gruyere or Swiss cheese slices, room temperature
1/2 cup
shredded Asiago or mozzarella cheese, room temperature
4 pinches
paprika