Prep the chicken: Pat chicken dry and season with salt, pepper, and 1 tablespoon ranch seasoning.
This builds flavor right from the start.
Blanch the green beans (optional but helpful): Bring a pot of salted water to a boil. Cook beans for 2 to 3 minutes until bright green and slightly tender. Drain and rinse with cold water.
Set aside. If skipping this step, plan to sauté beans a bit longer in the pan.
Sear the chicken: Heat olive oil in a large skillet over medium-high. Add chicken in a single layer.
Cook 3 to 4 minutes per side until golden and cooked through (165°F/74°C). Transfer to a plate and tent with foil.
Sauté the beans: Reduce heat to medium. Add butter to the skillet.
Toss in green beans and a pinch of salt and pepper. Cook 3 to 5 minutes, stirring, until crisp-tender and lightly blistered. Remove to the plate with the chicken.
Build the sauce base: In the same skillet, add garlic and cook 30 seconds until fragrant.
Pour in chicken broth and scrape up any browned bits. Stir in remaining 1 tablespoon ranch seasoning.
Make it creamy: Lower heat to medium-low. Whisk in cream and cream cheese until smooth and slightly thickened, 2 to 3 minutes.
Stir in Parmesan. If the sauce seems too thick, add a splash more broth.
Season and brighten: Add lemon juice and a pinch of red pepper flakes if using. Taste and adjust salt and pepper.
The sauce should be savory with a hint of tang.
Bring it together: Return chicken and green beans (plus any juices) to the skillet. Toss to coat and warm through for 1 to 2 minutes. The sauce should cling to everything without feeling heavy.
Serve: Finish with extra Parmesan and cracked black pepper.
Serve as-is, or spoon over rice, mashed potatoes, or buttered noodles.