Prep the ingredients. Trim the green beans, slice the onion, and mince the garlic. Cut the chicken into bite-size pieces and pat dry with paper towels. Season the chicken with salt, pepper, paprika, and thyme.

Heat the skillet. Add 1 tablespoon oil to a large skillet over medium-high heat. When the oil shimmers, it’s ready.

Brown the chicken. Add the chicken in a single layer. Don’t overcrowd; work in batches if needed. Sear 3–4 minutes per side until golden and mostly cooked through. Transfer to a plate and keep warm.

Sauté the onion. Add another tablespoon of oil if the pan looks dry. Add sliced onion and a pinch of salt. Cook 3–4 minutes, scraping up any browned bits, until the onions soften and pick up color.

Add green beans. Toss in the green beans and cook 3–5 minutes, stirring occasionally, until they turn bright green and start to blister. You want crisp-tender, not mushy.

Stir in garlic and spices. Add the minced garlic and a pinch of red pepper flakes. Cook 30–60 seconds, just until fragrant. Don’t let the garlic burn.

Deglaze with broth. Pour in the chicken broth and stir, scraping up the fond. Simmer 2–3 minutes to reduce slightly and allow the beans to finish cooking.

Finish the sauce. Stir in lemon juice for brightness and the butter for richness (if using). Taste and adjust seasoning with salt and pepper.

Return the chicken. Add the chicken back to the skillet, along with any juices on the plate. Toss everything together and cook 1–2 minutes more until the chicken is cooked through and the flavors meld.

Garnish and serve. Sprinkle with chopped parsley. Serve hot as-is, or with rice, mashed potatoes, quinoa, or crusty bread to soak up the sauce.