I was asked to make my brother-in-law's wedding cake in August. They would like a white cake with raspberry filling. Do professional cake decorators usually use a cake mix or from scratch? Do you have any recommendations? Any recommendations for a raspberry filling?
Pros use both, depending on their comfort level and customer base. There's no right or wrong, just don't mislead anyone.
Use whatever you are comfortable with.
Does your BIL and the bride to be have a preference? If they don't then I would bake with what you are comfortable with like KoryAK suggested.