Secret cipher that needs to be cracked

Slender or thin4 Slow-cooked meat dish4 "Saturday Night ___," NBC's sketch comedy show4 Ready-to-assemble furniture brand4 (5/6) You glance across the room and jump when you spot a face staring back, but it's just your own reflection in the vanity ___!6 Have a debt3 "Do you want an apple ___ banana?" (question at breakfast, maybe): 2 wds.3 (6/6) You freeze as a spine-tingling howl echoes through the house, but it's only the ___ rattling against the windows!4