？？
Is breakfast tomorrow bread or rice?
Literal
Tomorrow [possessive-の] breakfast [topic-は] bread [polite-です] [question-か]? Rice [polite-です] [question-か]?
Two parallel か-questions joined by context, offering a choice. Notice Japanese can frame a choice this way — 'Is it A? Is it B?' — rather than English's 'A or B?' ご飯 literally means 'cooked rice' but by extension 'meal' in general; here it's specifically rice as the alternative to bread.