Heat the oil in a large pot over medium heat.
Add in the garlic and saute for no more than 45 seconds (do not brown).
Add in the chicken broth and red pepper flakes.
Increase the heat to high and bring to a boil.
Add in the tortellini and cook for half the cooking time on the package.
Add in the tomatoes, reduce heat to medium-low and continue cooking until the tortellini is tender.
Stir in the spinach and cook until it wilts (about a minute).
Season if necessary with salt and pepper and serve.
The flavors of this soup are good immediately - something I don't usually find with soup - normally I like to let it sit a bit. The soup was just as good the following day!