INGREDIENTS
2 tsp
butter
1 tsp
vegetable oil
2
Spanish onions (about 1 pound), halved and thinly sliced
1/4 tsp
sugar
1/4 tsp
sea salt
1 tbsp
sherry vinegar
1/2 tsp
minced fresh thyme
3
applewood-smoked bacon strips
3/4 cup
shredded Gruyère cheese
1/2 cup
sour cream
1/2 cup
mayonnaise
1/4 tsp
freshly ground black pepper