Mix & Prep:

Start by combining the beef stock, bouillon cube, Worcestershire sauce, onion powder, thyme, and yellow mustard in a bowl or large measuring cup—set that aside. In a small container with a lid, shake together 3 tablespoons flour and 3 tablespoons cold water until smooth. Keep that chilled until ready to use. Rinse and pat dry your mushrooms, then slice if needed.

Prep the Chicken:

Slice each chicken breast horizontally to make thinner cutlets (you’ll get 2–3 pieces per breast). Pound slightly if needed so they’re even—aim for about ½ inch thick. Season both sides with salt and pepper, then dredge in flour, shaking off the excess.

Cook the Mushrooms:

In a large skillet over medium-high heat, melt the butter. Add the mushrooms in a single layer (work in batches if necessary). Let them cook undisturbed for 3–4 minutes on each side, so they get that beautiful golden brown color. Add a little butter or oil if the pan gets dry. Once they’re done, transfer to a plate and set aside.

Sear the Chicken:

Heat the avocado oil in the same pan. Cook the chicken in batches, about 4–5 minutes per side, until golden and cooked through. Don’t overcrowd the pan, and let the chicken sit undisturbed while it sears to develop a nice crust. Remove and set aside.

Deglaze the Pan:

Turn the heat off and pour out any excess oil—but don’t wipe the pan clean! Those browned bits at the bottom are key for flavor. Turn the heat back on to medium, add the wine and garlic, and use a spatula to scrape up everything stuck to the bottom. Let it bubble until reduced by about half, around 4 minutes.

Make the Sauce:

Pour in the prepared broth mixture. Turn the heat up just slightly and bring it to a gentle boil. Let it simmer for about 10 minutes to thicken slightly and deepen in flavor.

Thicken & Finish:

Give the flour-water mixture another good shake, then slowly pour it into the bubbling sauce while stirring. It’ll thicken quickly. Once it does, reduce the heat to low and stir in the heavy cream. Add the mushrooms back in and give it all a good mix.

Bring it Together:

Return the chicken (along with any juices) to the pan. Spoon sauce over the top, cover partially, and let it warm through for 5 minutes or so.

Serving Suggestion

This is delicious served over creamy mashed potatoes, egg noodles, or rice—don’t forget some roasted green beans or asparagus on the side to round it out.