3 carrots, thinly sliced
2 celery leaves
5 onions, thinly sliced
4 stalks celery, finely chopped
1 (16 ounce) can tomato paste
1 (6 ounce) can pesto, or to taste
Bring a large pot of lightly salted water to a boil. Add carrots and celery; cook and stir until tender, about 5 minutes. Remove carrots and celery; drain.
Place onions, celery, and carrots into the hot water with the onion mixture. Allow vegetables to steam.
In a large bowl, combine tomato paste, pesto and pasta. Mix with a metal spoon.