Heat oil and 1 tbsp butter in skillet over medium-high heat. Season chicken breasts with salt and pepper, add to pan and sear until golden, about 4 minutes each side. Remove chicken from pan and set aside. Add remaining butter and onion, apple, garlic, thyme, and bay leaves. Saute until apple begins to color and onions soften, about 6 minutes. Add flour and stir 2-3 minutes. Add chicken back to pan, add cider, bring to a boil, reduce to a simmer and cover. Cook until chicken is done through, about 12 minutes.