Combine shredded cabbage, carrot, and green onions. Whisk apple cider vinegar with honey and a pinch of salt, then toss with the slaw and set aside.
Heat olive oil in a large skillet over medium-high heat. Season chicken with salt, pepper, and garlic powder. Sear in the hot pan until cooked through, about 5–7 minutes total depending on size.
Lower heat, add butter if using, then pour in buffalo sauce and toss chicken to coat. Remove from heat to prevent sauce from reducing too much.
Arrange lettuce leaves, spoon slaw into each leaf, top with buffalo chicken, and drizzle with ranch or blue cheese. Garnish with celery and herbs if desired. Serve immediately.
Notes
To make ahead, store chicken and slaw separately and assemble when ready to eat.
Swap in shredded rotisserie chicken as a time-saving option.
For a milder sauce, mix buffalo sauce with honey or melted butter.