Make Chili Oil: Heat ¼ cup olive oil in a small saucepan. Add minced garlic and chili flakes; sauté for 2-3 minutes. Set aside.

Caramelize Onions: In a skillet, heat 2 tbsp olive oil over medium-low. Add sliced onions and salt; cook for 20-25 minutes until golden brown.

Cook Pasta: Boil salted water in a pot, add pasta, and cook until al dente (8-10 minutes). Reserve 1 cup pasta water before draining.

Combine Ingredients: Add sautéed garlic to onions, cook for 1-2 minutes. Drain pasta, add to skillet and combine with onions.

Finish: Drizzle infused chili oil over pasta, toss to combine. Adjust seasoning with salt or chili flakes. Serve hot.