Prepare the sauce so it's ready to go when you're ready to add it, in a 1 cup measuring cup add wine, chicken broth, and cornstarch and whisk until smooth.
Heat skillet, I use cast iron as I like how it sears the chicken, add in the oil and place the chicken in skillet.
Allow the chicken to brown on each side.
Add in sliced mushrooms.
Turn the temperature to medium-low, then add in the sauce and bring it to a simmer.
Add in the cream and turn the chicken over to coat evenly.
Add in the broccoli, cover with a lid, turn on low and cook until the chicken has an internal temperature of 165°.
Then add rosemary, salt, and pepper.
The thinly sliced chicken will cook quickly, if you use thicker chicken it'll take a little longer to cook.