In a large pot with generously salted water, cook dried bucatini to al dente per instructions on packaging.

In a large sauté pan render the fat from the pancetta on medium heat, 5-7 minutes. Add red onions and cook until soft. Add chopped vine tomato, passata and tomato paste. Salt and pepper to taste. Add cooked bucatini, reserving 1/4 cup pasta water. Bring heat to high, add reserved pasta water and toss until bucatini is fully coated. Serve and garnish with freshly chopped parsley and cracked black pepper.