In a large pot of boiling water, cook the tortellini according to package's directions. Drain and set aside.
Meanwhile, as the tortellini is cooking, melt the butter in a large skillet set over medium-high heat.
Add the mushrooms and sauté for 4-5 minutes or until browned. Add the drained tortellini and cook until lightly toasted and browned around the edges. Add the garlic and cook just until fragrant.
Remove from the heat and stir in the pesto, basil and parmesan. Serve immediately.
Notes
Want to up the protein? Serve this with a grilled chicken breast!