When summer squash isn’t in season, use zucchini or even butternut squash, which will become tender in the same time if cut into ¼-inch-thick pieces. If you want to make this soup vegan, simply omit the bacon, use 6 tablespoons of olive oil instead of the amount of butter called for below, and use almond or soy milk instead of whole milk.
Summer Squash Chowder
Heat the bacon in a large saucepan over medium heat and cook, stirring occasionally, until crisp, about 12 minutes. Remove the bacon with a slotted spoon and reserve for garnish, leaving the bacon fat in the pot.
Melt the butter in the bacon fat, then add the thyme, garlic, celery, onion and bay leaf and cook, stirring occasionally, until the aromatics soften, about 6 minutes. Stir in the squash, then cover the pot partially, and cook, stirring occasionally, until the squash is softened and reduced in volume by one-third, about 15 minutes. Uncover, increase the heat to medium-high, and continue cooking, stirring as needed, until the liquid in the pot is concentrated and mostly evaporated, about 10 more minutes.
Pour in the milk, and bring the chowder to a simmer. Reduce the heat to maintain a gentle simmer, and cook, stirring occasionally, to marry flavors and reduce the milk slightly, about 10 minutes. Remove the bay leaf and then use an immersion or standing blender to puree the soup. Stir in the vinegar and season the soup with lots of salt and pepper.
Just before serving, thinly shave the patty pan squash crosswise. Pour the soup into bowls and garnish each with a few slices of shaved patty pan, some of the reserved bacon and a sprinkling of parsley to serve.