INGREDIENTS
3 tbsp
salted butter
2
yellow onions
1 serving
kosher salt
3/4 cup
apple cider
1 tbsp
fresh thyme leaves
1 tbsp
fresh sage
1 pinch
red pepper flakes
8 slices
sourdough bread
2 tbsp
extra virgin olive oil
1 1/2 cups
fontina cheese
1 1/2 cups
white cheddar cheese
1
apple