Heat 1 tablespoon of olive oil in your pot over medium heat. Add the diced onion and sauté for about 3-4 minutes or until translucent. Toss in the minced garlic and cook for another 30 seconds until fragrant but not browned.
Pour in the 2 cups of fire-roasted diced tomatoes along with their juices. Stir in the dried basil, dried oregano, salt, and black pepper. Let this mixture simmer for 2 minutes to allow the flavors to meld beautifully.
Add 4 cups of chicken broth to the pot and increase the heat to bring the soup to a gentle boil.
Carefully add the package of cheese tortellini straight into the boiling soup. Cook according to the package instructions, usually around 3-5 minutes, until the tortellini are tender and cooked through.
Once the tortellini are cooked, stir in 1 cup of fresh spinach. Let it wilt into the soup for about a minute.
Ladle the soup into bowls and sprinkle generously with grated parmesan cheese if you like.
