Prepare all of the vegetables aside from the tomatoes.

Sauté the onion, leek, and pancetta. Pour in the broth, potato, carrots, thyme, 2tsp salt, and ¼ tsp pepper. Bring to a boil; skim if needed, and add white beans. Simmer for 25 minutes following steps below.

When 20 minutes are left, add the green beans. When 10 minutes are left, add the chopped zucchini and pasta shells. Taste at the end and adjust spices; may need more salt and red pepper flakes work well. (I think I also added a chicken bouillon cube for good measure; remember this soup takes 2-3 hours simmering typically and needs much more salt upfront in my cheater, 1-hour version.)

While the soup is cooking: Score, blanch until skins start peeling, rinse in cold water, peel, seed, and dice the tomatoes, then place them in a colander to drain any extra juices. (Skip if using canned; just chop in half, drain seeds/juice, and dice in that case.) Add half of the tomatoes to the soup at any stage.

Add the garlic, basil leaves, and a soft piece of potato from the soup to a food processor/blender. Mix well. Season with salt and pepper, and gradually add the olive oil, taste and adjust. When the mixture thickens and tastes downright zesty, stir it into the tomatoes in a large bowl. This is your pistou!

Taste and adjust the soup spices one last time. Remove the pot from the heat, and serve in bowls with Gruyère, spoonfuls of that beautiful pistou, extra chopped basil, red pepper flakes, and a drizzle of olive oil.