Boil and drain pasta under running water.
NOTE: The water stops the cooking process and thus prevent soggy overcooked pasta.
Heat the oil and saute the onions until translucent.
Then add the pimento peppers, celery, chadon beni pesto, salt and pepper to taste.
Mix the ingredients thoroughly. Cook for 3 minutes.
In a large bowl mix well the chadon beni pesto mixture into the pasta.
Then mix in the grated Parmesan cheese. Serve hot.