Martin survived on Sweetened Rice pudding and i used to make him Semolina pudding. (sorry the recipe is in litres and gramms)
1 litre of heated milk, and 150 grs of sugar stir until disolved, add 100 gr of semolina and bring to the boil for about 7 minutes, stir continuaously, add vanilla extract. In the bottom of ramequins or cups add maple syrup to cover the bootm of the cup. Add the semolina mix, put in the fridge and wait for it to settle.
He did end up with the PEG because he couldn't swallow at all in the end but it did help for a while.
Otherwise custard with maple syrup.