In a large pot over medium heat, crumble the Italian sausage into the pot. Cook, stirring occasionally, until the sausage is nicely browned and cooked through, about 5-7 minutes. Once done, use a slotted spoon to remove the sausage from the pot and set aside, ensuring to leave the rendered fat in the pot for added flavor.
In the same pot, add the diced onion, diced carrots, and diced celery. Sauté the vegetables for approximately 5-7 minutes until they are tender and the onion becomes translucent, stirring occasionally to prevent sticking.
Add the minced garlic, dried oregano, dried basil, and red pepper flakes to the pot. Stir well and cook for an additional minute until the garlic is fragrant and the herbs are aromatic.
Carefully pour in the chicken broth along with the can of diced tomatoes and their juice. Increase the heat to bring the mixture to a rolling boil.
Once boiling, add the small pasta of your choice. Reduce the heat to a gentle simmer and cook according to the pasta package instructions, typically around 8-10 minutes, until the pasta is cooked al dente. Stir occasionally to ensure even cooking.
After the pasta is done, return the cooked sausage to the pot and add the fresh chopped spinach. Stir together and cook for an additional 2-3 minutes until the spinach has wilted and integrated nicely into the soup.
Finally, taste the soup and season with salt and black pepper as desired.
Notes
Serve hot with grated Parmesan cheese and crusty bread.