1.Preheat oven to 200°C (180°C fan forced). Grease and line two oven trays.
2.Cook kumara in a heated oiled large frying pan over high heat, stirring, until browned lightly and tender. Combine kumara, spinach and corn in a large bowl.
3.Cut pastry sheets into quarters. Place equal amounts of filling near the centre of each square. Lightly moisten pastry edges with a little water, fold pastry in half to form a triangle. Press edges together with a fork to seal.
4.Place triangles on trays, spray with oil. Bake triangles for 15 minutes or until browned lightly.
You can substitute potato or pumpkin for the kumara, or use a combination of all three it will be just as delicious. Triangles can be made a day ahead to the end of step 3, cover, and refrigerate until ready to bake.Note