Yam [taro] paste rolls

3 1/2 cups flour
2 tbsp milk powder
1 tbsp sugar
Pinch salt
1 tsp bread improver
1/2  cup warm water
1 egg
1/4 cup oil-add in last
For the yeast: mix and leave till frothy
1 tbsp instant yeast
1 tbsp sugar
1/2 cup warm water
Fillings and topping:
Yam paste
Sesame seeds
1.    For the dough ,pour the yeast mixture into the flour mixture except the oil. Knead well until combine, add oil and knead well until you get a smooth dough.
2.    Leave the dough to rise in double in a warm place. Punch down the dough and knead again. Divide the dough in half. Roll thinly in rectangle and cut into triangle shape, spread yam paste over the pieces and roll up from the wider area to the pointed end. Sprinkle with sesame seeds.
3.    Place in greased pan and leave to rise again, bake in preheated oven at 250 C for 10 min or till golden on the surface. Brush with butter, serve warm.
To make yam paste: peeled and cooked  800gm  yam in water till soft, mashed it . heat up 2 tbsp margarine and add yam and 1 1/2 cup sugar. Stir till thicken . it takes 1/2 hour.