Christ, is this what passes as 'food tech' in some schools?
Yes, DD has to take ingredients in, but it is usually sensible portions (except the lasagne, but she cooked that last lesson and it fed the whole family).
She had to make the tomato sauce from scratch, including prepping the tomatoes. She had to make the Béchamel sauce from scratch. This was the start of Y10 Catering GCSE.
In Y9 she made profiteroles from scratch, a whipped sponge, a creamed sponge, stir fry including researching a sauce too (she made sweet and sour sauce from scratch). Other dishes included shortcrust pastry, Cornish pasties, a chicken and bacon pie, an apple and blackberry pie, and others that I can't remember.
I do think, though, that you need to provide adequate equipment for your DD to bring the stuff home in if you want it brought home.
For all you know, your DD might not have said anything to the teacher until the rest of the class were filing out. If the teacher then dismissively told her to throw it away, then that is surely because it is your and your DD's job to ensure your DD has adequate equipment for her lessons, not the teacher's. You wouldn't expect your DD to turn up to a Maths lesson without a pencil, rubber and ruler, would you?!
Just hope that your DD doesn't do Catering GCSE - the ingredients get far more expensive at that point! Two course meals in a double lesson...