Step 1

Heat a large, heavy-bottomed pot over medium heat. Add the olive oil, onions, red pepper flakes, garlic and potatoes with a generous pinch of salt. Cook over medium heat, stirring with a wooden spoon, until the vegetables are tender, 3 to 5 minutes. Add the tomatoes and 2 cups water and continue cooking until the tomatoes start to break down and mellow out, 10 to 12 minutes.

Step 2

Add the beans, peas, corn and celery and simmer 2 to 3 minutes. Taste for seasoning.

Step 3

Transfer to serving bowls and garnish with a few dollops of pesto and a generous sprinkle of Parmesan cheese. Serve with garlic bread on the side if desired.