Place flour in a plastic bag and add the chicken, tossing the bag to coat the chicken.
Heat 2 tbs oil over medium-high heat in a large skillet. Add the chicken to the pan and brown well on each side, about 5 minutes per side. Remove the chicken to a plate.
Heat the remaining 1 tbs of oil to the skillet. Add the mushrooms and let them sear, stirring constantly. This should take about 3 minutes.
Deglaze the pan with the chicken stock then add the garlic, parsley, tomato, cheese and butter. Stir until butter is melted.
Add the chicken back to the pan and heat through. Serve immediately.
Notes
I used 1 tsp Better Than Bouillon low-sodium chicken and 1/2 cup water.