This cozy Italian soup, which we last featured in 2020, has been a member favorite. Its satisfying combination of flavors and textures makes it both comforting and filling.
Heat a Dutch oven over medium-high heat. Add first part of oil and then mushrooms. Saute mushrooms until golden brown and tender, 4 to 5 minutes. Set mushrooms aside and return pan to heat.
Add second part of oil and then onions, carrots, and celery to heated oil. Saute until onions soften, 3 to 4 minutes.
Add sausage and stir to combine. Saute until sausage begins to break down and brown in spots, 3 to 4 minutes. Stir in zucchini, Italian seasoning, thyme, and salt and cook until fragrant, ~1 minute more.
Pour tomatoes, stock, and reserved mushrooms over sausage and vegetables. Bring to a simmer. Simmer until zucchini is tender, 8 to 10 minutes.
Stir in spinach, lemon juice, and hot sauce (if using). Taste and season with some salt and pepper.