Combine the tortellini and broth in a large pot or Dutch oven. Bring the mixture to a boil over medium-high heat.
Once boiling, reduce the heat to medium-low, cover, and simmer for 8 to 10 minutes, or until the tortellini is cooked through and most of the liquid is absorbed. Stir occasionally to prevent sticking.
Stir in the butter, minced garlic, heavy cream, and Parmesan cheese. Cook for 2 minutes, stirring until the sauce thickens slightly and becomes creamy.
Add the frozen peas. Cook for 1 to 2 minutes, just until the peas are heated through.
Remove the pot from the heat. Season with salt and pepper to your preference.
Stir in the fresh parsley before serving immediately.
Notes
If you do not have heavy cream, you can substitute it with half-and-half, though the sauce will be slightly thinner.
For added flavor, add a pinch of red pepper flakes with the garlic.
You can substitute frozen peas with frozen chopped spinach or broccoli florets.