Flashbacks are tricky. Take the reader back to the past, show them something interesting and necessary, and bring them back without whiplash. I’m trying to write a scene where the heroine has a conversation with her cousin and while they talk, she is thinking about their past. Instead of a block of memory, the scenes are intercut (is that the right word?). He says something and she replies–while thinking of what he’d said before. Back and forth and back and forth without being choppy and making sense.