I use mashed sweet potato in everything to boost our vege intake. I add it to choc chip cookies, currys, everything!

I just found a recipe for vegetarian vegetable rolls:

Use 3-4 vegetables like

1 sweet potato
2 small potatos
1/2 brocolli
1/2 cup peas
puff pastry sheets
2 tsp curry powder
salt & pepper

Steam & mash all the veges and the cut the puff pastry into four pieces. Put 1 tablespoon of vegetable mix on the piece of puff pastry, fold into a tube and close ends with a fork. Brush with olive oil and poke with a fork at the top. Bake until puffed and slightly browned in a med/hot oven.