Peel, seed and cut butternut squash into chunks. Put squash in a steaming rack and steam for 10 minutes. Remove and place in a large bowl together with the sugar, butter, and half-and-half. Mash until you get a smooth paste. Mix in toasted pumpkin seeds. When cool, shape into 16 balls, approximately the size of a walnut.
In a large bowl, add flour, butter, powdered sugar, and salt. Cut in butter with pastry blender or two forks until resembles coarse bread crumbs. Add water and mix to form a soft, non-sticky dough. If dough is a little sticky, add a little more flour. Cover and set aside to rest for 20 minutes.
Place flour and salt in a separate bowl. Make a well in the center. Pour in oil and pandan paste. Mix to form an even colored dough. If it is too sticky, add a little more flour. Cover and set aside to rest for 20 minutes.
On a lightly floured surface, roll dough a into A circle about 8 inches (20cm) in diameter. Place dough B in the center of dough A. Gather up the sides of dough A to wrap over dough B. With seam side down, roll out ball of dough into a rectangle of about 9-in x 12-in (23cm x 30cm).
With the short side, fold dough facing you over by a third. Reach over and fold the other side over.
Turn dough 90° and roll out again into a 9-in x 12-in (23cm x 30cm) rectangle.
Again fold dough into third like the first time. Turn dough 90° and this time roll dough into a rectangle of about 14-in x 12-in (35cm x 30cm). With the long side, roll dough up into a cylinder.
With both hands on the cylinder, continue to roll until it is about 1¾ inches in diameter.
Cut off ends and slice cylinder into 16 pieces, each about ⅝ inch thick.
Roll out each piece of dough with cut side up into a circle of about 4 inches (10cm) in diameter. Place a ball of filling in the center. Gather up the edges to wrap around filling. Place seam side down onto a baking sheet. Repeat with the rest of dough and filling.
Bake in a 350°F (180°C) oven for 30 minutes or until lightly golden. Remove and let cool on wire rack.