I was really hoping someone with more knowledge would answer this, expect you've done this by now, but anyway here's what I think (please correct me anyone?!)
So the question in English would be
'What did you have for breakfast?' ( did implies 'this morning') or;
'What do you have for breakfast?' (do implies 'usually')
But there are no tenses in BSL, so you give the timeframe first:
'This morning [or usually] breakfast you eat what?'
I'm fairly sure of that part, the answer, less certain,
'This morning, Breakfast I toast eat' - at least I think it's that order, not 'eat toast', because the example of sentence order I often see is 'the cat tree climbs': Subject; object; verb - if you were drawing a picture you wouldn't draw the cat climbing, before giving it a tree to climb.