Heat the olive oil in a large, deep skillet over medium-high heat. Add the chicken and cook until browned on all sides and nearly cooked through, about 5 to 7 minutes. Remove the chicken from the skillet and set aside.
Add the sliced mushrooms and chopped onion to the same skillet. Cook until the mushrooms release their liquid and the onions soften, about 5 minutes.
Add the minced garlic and cook for 1 minute until fragrant.
Stir in the uncooked rice, coating it with the pan drippings.
Pour in the chicken broth. Bring the mixture to a boil, then reduce the heat to low, cover the skillet, and simmer for 15 minutes, or until the rice is tender and most of the liquid is absorbed. Do not lift the lid during this time.
Return the cooked chicken to the skillet. Stir in the heavy cream and Parmesan cheese. Cook uncovered for 2 to 3 minutes, stirring gently until the sauce thickens slightly and the chicken is heated through.
Remove from heat. Garnish with fresh parsley before serving.
Notes
If you prefer a thicker sauce, allow the mixture to simmer uncovered for an extra minute or two at the end.
Use pre-sliced mushrooms to save preparation time.
You can substitute chicken broth with vegetable broth for a slightly different flavor profile.