I've always loved custard of any kind, and banana cream pie was a real treat.
Alas, I don't eat custard anymore, except for custard sauce I make with low-carb milk in the summer when my raspberry bushes are producing. They don't raise my BG very much.
I recently invented a banana cream substitute when I was trying to use up some ricotta cheese I'd bought for another recipe.
Basically, you stir some DaVinci sugarfree banana flavoring into full-fat ricotta cheese. (I find the Maggio brand is the creamiest I can get here.) Top with sugarfree whipped cream. And that's it. Pretty simple.
The ricotta has a smooth texture somewhat like custard, and when topped with sugarfree whipped cream, it really gave me the feeling I was eating banana cream.
I like the sugarfree whipped cream that comes in a can, made by Land O'Lakes, because I can use just a little at a time. You can get it at Walmart superstores. When I buy heavy cream and whip it, then I have to use up the rest of the cream or it will go bad. So I end up eating more heavy cream than I really want.
You do have to be careful with ricotta cheese, as it does contain some carbs, so small portions are in order. It was so good I went overboard, and my BG levels did reflect that.
But it made a nice change for me, and next time I'll be more careful.