>And ... what the h--- is/are cream (creme) tarts?

Cream cakes is a generic term for anything that you get from a cake shop with cream in it. If it were made of sponge it would be a cream sponge. Tarts tend to be made with a pastry case. Individual strawberry or fruit tarts are popular and they would have a dollop of cream on top. I think that people would be more likely to refer to the kind of fruit, rather than the cream.

I rather suspect that the episode was written by a man! (ouch, waiting to be told I'm sexist)