Oh, my... I know that she gets played to death, and has her lion's share of recommendations on these pages, but I have to mention this one.
For an artist considered sexy in any context this really takes it high. The track just makes you wanna light the candles, pour the cava, burn the buddah, and get freaky-sticky all over the couch! I mean come on! A total love down... Reminds me of the best stuff from the Moments/Sylvia Robinson camp... Smooth smooth soul. And with one of the most sultry voices in recorded history, it's just insane.