Finely slice the vegetables and fry in some oil until soft. Warn the refried beans in a saucepan adding the tomato ketchup. This sweetens the mixture and also adds some moisture - this helps to stop the mixture drying out too much as it cools, in my experience children like their food to be cold before eating it and refried beans go too dry if left to get cold. Spread some of the refried bean mixture on a tortilla and then place on some of the vegetables. Roll it up and serve with mayonnaise
If you have left overs make up the wraps and put the in the fridge. Cover with some melting vegan cheese and bake in the oven for 20 minutes.