Put the milk, pumpkin, oil and eggs into a large mixing bowl and whisk until become a smooth texture, then add the sugar, flour, baking powder, cinnamon, salt and nutmeg. Whisk to blend then add the liquid ingredients and whisk again. Lastly add the walnuts and let the texture rest for about 5 min before using it.
Preheat the waffle maker to the desired setting.
Pour 2 cups of the mixture in the center of the lower grid of the preheated waffle maker and spread evenly, than close the lid. When ready carefully remove the waffle and repeat with the remaining mixture. For best results, serve immediately.