Add olive oil to a large pan on medium heat and brown the mushrooms and onions- about 4 minutes and set aside.
Next brown the chicken on both sides (about 4 minutes each side). Set aside.
Add butter, chicken broth, and cream to pan (still on medium heat) and bring to a simmer, stirring occasionally. Add garlic, rosemary and mushroom mixture and simmer for 5 minutes, continuing to stir.
Add chicken back to the pan and scoop some of the sauce over the chicken.
Place in oven for 10 minutes to finish cooking.
Sprinkle with red pepper flakes if desired.
Serve with rice or noodles or grilled veggies and enjoy!
Recipe by My Frugal Adventures at https://myfrugaladventures.com/2016/10/creamy-garlic-and-rosemary-chicken/