I usually eat porridge but will have an english breakfast occasionally or smoked haddock and poached egg. I also like toasted rye bread and boiled eggs. The rye bread and porridge are unrefined carbs that release slowly but it is important not to follow up these foods with consecutive meals also with too many slow release carbs. They do build up.
If you have got the time, a full english breakfast is surprisingly one of the things diabetics can have. Just avoid the fried white bread and toast and marmelade.
And tea, a big pot or mug of tea. If you are not into tea, get into it. It's the king of drinks.