Ingredients:

  • 3 large yellow onions, thinly sliced (approx 1.5 lbs / 680g)
  • 3 tbsp unsalted butter (42g)
  • 2 tbsp olive oil (30ml)
  • 1/2 tsp kosher salt (3g)
  • 1/4 tsp granulated sugar (1.5g)
  • 12 oz linguine or fettuccine (340g)
  • 4 cloves garlic, minced (20g)
  • 1/2 cup freshly grated Parmesan cheese (50g)
  • 1 tbsp fresh lemon juice (15ml)
  • 2 tbsp fresh parsley, chopped (30g)

Instructions:

  1. Bring a large pot of salted water to a boil. Slice yellow onions into thin, uniform half-moons.
  2. Melt butter and olive oil over medium-high heat in a large heavy-bottomed skillet. Add onions and salt, sautéing for 5-7 minutes until translucent.
  3. Reduce heat to medium, stir in the sugar, and cook for 10-15 minutes, stirring occasionally, until onions reach a deep mahogany hue.
  4. Cook pasta until 1 minute before al dente. Reserve 1 cup of starchy pasta water before draining.
  5. Add minced garlic to the caramelized onions and cook for the final 60 seconds.
  6. Toss the drained pasta into the skillet with the onions. Pour in 1/2 cup of reserved pasta water and the Parmesan cheese.
  7. Toss vigorously over medium heat until the sauce emulsifies into a velvety glaze. Stir in lemon juice and parsley just before serving.