Add gluten-free flour, sugar, gluten-free baking powder, and salt to large mixing bowl. Whisk ingredients together until well incorporated. Set dry bowl aside.
Add melted butter, milk of choice, eggs, and pure vanilla extract to medium bowl. Whisk ingredients together until thoroughly combined.
Slowly add wet ingredients to large bowl with dry ingredients, whisking or mixing well to thoroughly incorporate both mixtures before adding more. Continue process until entire mixture of wet ingredients has been incorporated into dry ingredients to form smooth waffle batter.
Preheat waffle maker. Let waffle batter sit while waffle maker preheats.
When waffle maker is preheated, lightly spray waffle maker with gluten-free cooking spray. Use ladle or cookie scoop with release handle to portion batter into greased waffle maker. Amount of batter used will depend on size of waffle maker.
Close waffle maker and cook according to waffle maker instructions, or until waffles are golden brown and cooked through. Use fork to carefully lift cooked waffles out of waffle maker, and transfer waffles to plate. Set plate aside and repeat process until all batter has been used.
Serve waffles warm with desired toppings and desired sides. Alternately, let waffles cool completely then refrigerate or freeze waffles for later (see Notes).