In a small bowl, add warm whole milk and 1 package active dry yeast. Whisk together to dissolve and set aside.
In a mixing bowl, add flour, pumpkin pie spice, and salt. Stir to combine. Add milk and yeast mixture, melted butter, eggs, vanilla, and pumpkin. Stir together well, cover, and let rise in a draft free area for at least 30 minutes, but no longer than 45 minutes.
Uncover dough and fold in the pearl sugar. Dough will be sticky.
Lightly oil waffle iron and preheat according to your waffle iron's instructions. You only need to oil it once at the beginning. The dough contains quite a bit of butter, so the waffles will not stick during baking.
Divide dough into 8 large balls, or use a large metal scoop to place dough balls into hot waffle iron. I use a Cuisinart Electric Belgian Waffle Maker and set the temperature between 4 & 5. The waffles need to bake at least 3 minutes each, maybe longer. Make sure the waffles are nice and brown to insure doneness. The pearl sugar will melt and caramelize on the outside of the waffles. Have no fear! The melted sugar on the waffle grid will not burn, just caramelize on the waffles. No need to wipe the grid between baking each waffle. Wait until the iron cools almost completely before cleaning.
Enjoy these delectable treats right away, and store any leftovers in a ziploc for the next day. Warm leftovers (if you have any!) in the oven for a few minutes.