One Pot French Onion Pasta

Instructions

1. 1
   Melt butter with olive oil in a large pot over medium heat. Add onions, salt, pepper, and sugar. Cook, stirring often, for 15–20 minutes until deeply golden and caramelized.
2. 2
   Stir in garlic and thyme. Cook for 1 minute until fragrant. Add balsamic vinegar, scraping up any browned bits from the pan.
3. 3
   Add dry pasta and broth to the pot. Stir well, bring to a boil, then reduce heat to a gentle simmer.
4. 4
   Cook uncovered, stirring occasionally, for 10–12 minutes until pasta is al dente and most of the liquid has been absorbed.
5. 5
   Turn off the heat. Stir in Gruyère and Parmesan until melted and creamy.
6. 6
   Taste and season as needed. Serve hot, garnished with more cheese and fresh herbs.