Heat a tablespoon of olive oil in a large, deep skillet over medium heat. Add onion and cook, stirring often, until softened; 3-4 minutes. Stir in minced garlic and cook for 30 seconds. Add sausage and cook until browned on both sides.

Stir in chicken broth, tortellini, tomatoes, and a pinch of salt and pepper. Bring to a boil, stirring often. Turn heat to low, cover and simmer for about 10-15 minutes, or until pasta is tender, stirring at least once to prevent sticking. *There should still be liquid in the pan to make the sauce, but if it seems excessive, you can remove some with a large spoon. (If you want a quicker cooking method, set at medium-low heat, uncovered, stirring often for about 8-10 minutes).

*If there is too much liquid left in the pan, spoon some out. But be sure to leave enough behind to make the sauce.

Remove from heat and stir in cheeses, reserving a handful for sprinkling on top. Cover and let stand for five to ten minutes, or broil for 2-3 minutes to brown. Garnish with fresh parsley, if desired.