Are you newly diagnosed? Or do you have problems with hypos overnight?
8 is a bit higher than the normal pre bed target (which I think is 6 according to DAFNE) but if you answer yes to either of the above then those are good reasons to have cautious targets.
Have you got any idea how many grams of carbs you need to bring you up 1 mmol/L? If you can work that out, then you can work out what you need to eat - for example, if you need 5g of carbs to bring you up 1 mmol, you are at 5 and you want to be at 8, you need to find something with 15g of carbs.