01 -
Combine beef broth, chicken bouillon, soy sauce, onion powder, mustard powder, and thyme in a bowl. Set aside. Mix cornstarch with 3 tablespoons of cold water in a sealable container, shake to combine, and set aside. Gently rinse mushrooms, pat completely dry, and slice if necessary. Slice chicken lengthwise into 2-3 thinner pieces about ½ inch thick, pounding with a meat tenderizer if needed.
02 -
Melt butter over medium-high heat and add mushrooms. Allow them to brown undisturbed on each side for 3-4 minutes. Cook in batches if necessary to ensure proper browning, adding more butter or olive oil as needed. Remove golden brown mushrooms and set aside.
03 -
Season chicken with salt and pepper on both sides. Dredge in flour, tapping off excess. Heat olive oil in a large pan over medium-high heat. Sear chicken in batches (3 pieces at a time) for 4-5 minutes per side until golden brown with a crust formed. Remove chicken and set aside.
04 -
Turn off heat and remove excess oil, preserving brown bits (fond) in the pan. Add white wine and garlic, setting heat to medium. Scrape bottom of pan with a silicone spatula to loosen browned bits. Allow mixture to reduce by half, about 4 minutes.
05 -
Add beef broth mixture and bring to a gentle boil. Simmer for about 10 minutes to reduce. Shake cornstarch mixture and slowly pour into bubbling sauce while stirring continuously until fully incorporated. Reduce heat to low, then slowly stir in cream. Return mushrooms to the pan. Add chicken and any accumulated juices back to the pot, spooning sauce over the chicken. Cover partially and heat through for about 5 minutes.