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Creamy Caramelized Onion Pasta Recipe

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4.1 from 15 reviews

A luscious and comforting creamy caramelized onion pasta featuring slowly caramelized onions, a silky cream and parmesan sauce, fresh thyme, and bright lemon notes. Perfect for a cozy dinner, this recipe balances sweetness from the onions with subtle heat from red pepper flakes and the freshness of lemon zest, all tossed with perfectly al dente pasta.

  • Total Time: 1 hour
  • Yield: 2 servings

Ingredients

Pasta

  • 200 grams dried pasta (or 300 grams fresh)

Caramelized Onions

  • 1 tablespoon olive oil
  • 1 tablespoon butter
  • 2 medium onions (about 450 grams total)

Sauce

  • 1 tablespoon butter
  • 2 garlic cloves, minced
  • 1/4 teaspoon red pepper flakes (optional)
  • 2/3 cup heavy cream
  • 50 grams parmesan cheese, very finely grated
  • 1 tablespoon fresh thyme leaves, roughly chopped
  • 1 tablespoon lemon juice
  • Salt and pepper to taste
  • Lemon zest, for serving (optional)

Instructions

  1. Caramelize the Onions: Trim both ends off the onions, cut in half lengthways, peel, then slice each half into ¼-inch thick half circles. Heat 1 tablespoon olive oil and 1 tablespoon butter in a heavy bottomed skillet or Dutch oven over medium heat. Add onions and cook for 10 minutes until softened. Mix in salt, reduce heat to low, and cook for 40 more minutes until the onions are golden and very soft, stirring often to prevent burning. If they start to dry out, add a splash of water. Set aside when done.
  2. Cook the Pasta: Bring a large pot of well-salted water to a boil. Add pasta and cook, slightly undercooking by about 1 minute less than package instructions. Reserve 1 cup of pasta water before draining the pasta.
  3. Prepare the Sauce: When pasta has about 5 minutes left to cook, return the skillet with the caramelized onions to medium heat. Add minced garlic and red pepper flakes (if using), cooking gently for 1 minute until fragrant but not browned. Pour in heavy cream and bring to a very gentle simmer, adjusting heat so it never boils. Stir in fresh thyme leaves.
  4. Add Parmesan: Gradually add parmesan cheese in 2-3 additions, stirring well and allowing it to melt between additions until the sauce is smooth and creamy.
  5. Combine Pasta and Sauce: Add the drained pasta, caramelized onions, lemon juice, and ¼ cup reserved pasta water to the sauce. Toss everything well to combine.
  6. Finish Cooking: Let the pasta and sauce bubble gently over low heat for 1-2 minutes to finish cooking the pasta and thicken the sauce. Add more pasta water if needed to loosen the sauce, keeping it saucy as it will thicken quickly off the heat.
  7. Season and Serve: Taste and adjust seasoning with salt and pepper. Serve immediately, topped with extra grated parmesan and lemon zest if desired.

Notes

  • Stir onions frequently while caramelizing to avoid burning.
  • A splash of water during caramelization prevents onions from drying out.
  • Undercooking pasta slightly before finishing in sauce helps achieve perfect texture.
  • Do not let the cream boil to avoid curdling and to maintain a smooth sauce.
  • Optional red pepper flakes add subtle heat but can be omitted for a milder flavor.
  • Use freshly grated parmesan for best melting and flavor.
  • Lemon zest adds a bright finishing touch and enhances flavors.
  • Author: Monica
  • Prep Time: 10 minutes
  • Cook Time: 50 minutes
  • Category: Main Course
  • Method: Stovetop
  • Cuisine: Italian

Find it online: https://monicarecipes.com/creamy-caramelized-onion-pasta-recipe/