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This Caramelized Onion Pasta is a beautiful marriage of simplicity and deep flavor. Slowly cooked onions turn golden and sweet, then get tossed with al dente pasta, butter, Parmesan, and a hint of balsamic vinegar for brightness. It’s rich without being heavy—perfect for a weeknight dinner or a comforting date-night meal at home.

🧅 Ingredients

• 3 large yellow onions, thinly sliced
• 3 tablespoons olive oil
• 2 tablespoons unsalted butter
• Salt and black pepper, to taste
• ½ teaspoon red pepper flakes (optional)
• 12 oz spaghetti or linguine
• 1 tablespoon balsamic vinegar
• ½ cup grated Parmesan cheese (plus extra for garnish)
• Fresh parsley or thyme for garnish (optional)

🔥 Instructions

Caramelize the Onions: In a large skillet over medium-low heat, warm olive oil and butter. Add the sliced onions and a pinch of salt. Cook slowly, stirring occasionally, for 30–40 minutes, until onions are deep golden brown and caramelized. Add red pepper flakes if you like a little heat.

Boil the Pasta: While the onions are caramelizing, cook your pasta in salted boiling water according to the package instructions. Reserve 1 cup of pasta water before draining.

Deglaze & Combine: Once the onions are ready, stir in the balsamic vinegar to deglaze the pan. Add the cooked pasta directly to the onions, tossing to combine.

Creamy Finish: Add the Parmesan and a splash of reserved pasta water. Toss until the cheese melts and the sauce clings to the pasta. Add more water as needed for a silky texture. Season with salt and pepper to taste.

Serve: Plate the pasta and top with extra Parmesan and a sprinkle of fresh herbs if desired.

📦 Amazon Must-Haves to Help You Create the Best Caramelized Onion Pasta

• 🧅 Mandoline Slicer – Get evenly thin slices of onion with minimal effort.
• 🍝 Premium Spaghetti Pasta – Authentic texture and flavor for a true Italian base.
• 🧂 Balsamic Vinegar of Modena – Adds a tangy sweetness to balance the onions.
• 🧀 Grated Parmesan Cheese – A nutty, salty finish that ties it all together.
• 🍳 Nonstick Skillet – Ideal for caramelizing without burning.

💡 Helpful Tip: Be patient when caramelizing onions—don’t rush the process. Low and slow is the secret to unlocking their natural sweetness and achieving that deep golden color!