Caramelized onions and roasted garlic add sweet depth to Rach's hearty potato soup that's finished with a layer of gruyere and broiled to perfection.
Want more French Onion ideas? Try Rach's French Onion Dip Mashed Potatoes here.
For the roasted garlic, preheat oven to 425˚F. Cut off ends of garlic bulbs to expose cloves and top with thyme, salt, pepper and EVOO. Wrap in foil pouch and roast 45-60 minutes, or until soft and golden. Cool garlic, remove from skins and paste with knife.
For the onions, halve, peel and thinly slice the onions by hand or with mandolin or wide slicer of box grater.
Heat large skillet over medium to medium-low heat, melt butter, add onions, season with salt, white pepper, thyme and bay, and cook until caramelized, about 45 minutes, stirring frequently. Add sherry and raise heat, let it absorb, add wine and let it reduce by half a minute or so then remove pan from heat.
For the soup, place potatoes in soup pot and cover with water, bring to boil, salt water and cook to just tender, 10 minutes, drain. Return pot to heat and melt butter over medium to medium-high heat, whisk in flour, then add nutmeg and whisk in milk and stock, add ¾ of the potatoes and pasted, roasted garlic and cook soup to thicken a bit, 15-20 minutes over low heat. Add ¾ onions and stir.
Preheat broiler and line a baking sheet with foil or parchment. Fill oven-safe soup bowls with potato soup and top with remaining potatoes, onions and cheese, broil to brown, add more thyme and serve.