Hi Cass - here is a recipe i found in the Feedin your Baby and Toddler cookbook (by Annabel Karmels)
200g sweet potato peeled
100g pumpkin, peeled
150g potato
75g leeks, white part only, finely chopped
150g mushrooms, chopped
2 tbsp chopped parsley
125g bread crumbs
1/2 teaspoon soy sauce
1/2 lightly beaten egg
flour for coating
vege oil for frying

1 Grate the sweet potato, pumpkin and potato. Using your hands, squeeze out some of the excess moisture from the grated pulp
2 In a mixing bowl, combine all the vegies with the parsley, breadcrumbs, soy sauce and beaten egg. season to taste
3 form the mixture into about 12 walnut sized rissoles. Spread the flour on a plate and use to coat the rissoles lightly.
4 heat the oil in a large frying pan, add the rissoles and saute over a medium heat for 8-10 minutes, turning occasionally, until golden on the outside and cooked through.

(these are suitable for freezing)