In a large bowl combine flour, sugar, dried yeast, salt and cinnamon. Add milk, water, eggs, pumpkin puree and melted butter. Stir to combine and knead until the dough is soft, a bit sticky but quite elastic and pulls away from the sides of the bowl.
Transfer the dough to an oiled bowl, cover with plastic wrap and let it rise for about 1 hour in a warm area, until doubled in size.
Punch dough down and divide into 2 equal parts. Shape them into balls. On a floured surface roll each part into a 15-16 inch (38-40cm) circle, using a rolling pin. With the back of a spoon or a spatula, spread 2 tbsp (30g) softened butter onto each rolled dough. Using a pastry wheel cutter, cut 12 equal triangles (like slicing a pizza).
Make a small slit in the centre of each triangle base.
Roll each triangle into crescents, starting from the outside edge of the triangle. Once rolled place on a parchment paper lined baking sheet with the tip tucked down and under the roll. Repeat rolling with the rest of the triangles.
Cover with a kitchen towel and let them rise for about 20-30 minutes.
Meanwhile preheat the oven to 400F (200C).
Bake crescent rolls for 14-18 minutes until puffed and golden brown. While still warm, melt additional 1 1/2 tbsp (20g) butter and brush the tops of the rolls with it.
Let them cool for a few minutes before serving.