Caramelized Onion Pasta

1: Slice the onions and cook them in butter over medium heat until caramelized, about 40 minutes.

2: In a blender, combine the caramelized onions, olive oil, egg yolks, grated Parmesan cheese, water, salt, and pepper. Blend until smooth, adding more water if needed.

3: Toss the cooked pasta with the sauce in a large pan and warm over low heat for about 1 minute.

4: Garnish with fresh parsley if desired.