Are "che", "che cosa" and "cosa" interchangeable in simple "what questions"?

Question

When I want to ask "what do you have for breakfast?", can I use any of the three, "che", "che cosa", or "cosa", to ask the question?I'm not referring to specific structures like "che ore sono?".

Answer 1

"Che cosa" is the technically right answer, and "cosa" would also be fine because "che" is often left out colloquially. "Che" can't be used on its own here, though.