French Onion Fondue: Caramelized and Silky for 8 Servings

Instructions:

1. In a large heavy-bottomed skillet, melt butter and olive oil over medium-low heat. Add sliced onions and sugar.
2. Cook onions for 35–40 minutes, stirring occasionally, until soft and a deep mahogany brown. Deglaze with a tablespoon of water if sticking occurs.
3. Stir in minced garlic and sherry vinegar during the last 2 minutes of onion cooking, then remove from heat and set aside.
4. In a large mixing bowl, toss the grated Gruyère and Gouda with cornstarch until every strand is evenly coated.
5. In a fondue pot or ceramic-coated saucepan, bring the white wine, Dijon mustard, and nutmeg to a light simmer over medium heat.
6. Gradually add the cheese mixture one handful at a time, whisking in a figure-eight motion until fully melted and emulsified before adding the next batch.
7. Fold in the caramelized onion reduction and fresh thyme. Serve immediately while warm.