Cook the pasta according to the package instructions. Add the spinach during the last minute of cooking.

Transfer the cooked pasta and spinach to a serving plate.

Add 1 tablespoon of mayonnaise to a frying pan and stir-fry the onion and cooked spinach.

Once the ingredients are somewhat cooked, add the cooked pasta and 2 tablespoons of mayonnaise. Continue to stir-fry until slightly colored.

Season with salt, pepper, and black pepper to taste, and it's ready to serve!