Baking Banana Bread
When having sexual relations with a women; the penis is termed "banana" and the vagina is the "bread." "Baking" is simply the sexual act. This term is commonly referred to in conditions when saying "i fucked the shit out of that bitch" would be innappriotate
"Hey whats up man... did you bake banana bread with suzy last night?"
"Yea, I did... we made several loafs."
"Yea, I did... we made several loafs."