Mix flour, baking powder, soda, salt, ginger and cinnamon in a bowl. (If using the crystalized ginger remove 2 Tbsp of flour mixture and toss the ginger and flour together and then set aside).
Whisk eggs, buttermilk, melted butter, pumpkin, sugar and vanilla in another bowl.
Combine flour with pumpkin mixture. Stir in butter and fold in crystallized ginger mixture (if using). Do not overmix. Heat a waffle iron and make waffles, using about 1/2 cup batter per each one. Keep warm in 200°F oven, if desired.