Add the cooled butter, beat for another minute, then remove the bowl from the mixer.
Sift the flour and baking powder into the bowl and stir well. The batter/dough will be stiff.
Heat the pizzelle maker according to the directions. When ready, scoop some of the dough onto the center of each pattern (I used an OXO 1.5 tbsp ice cream/cookie dough scoop so that each one would be the same size), and cook as directed, about 1 1/2 to 2 minutes usually. The pizzelle should be pale, with a slight golden tinge to them.
If you want traditional pizzelle, just place them on a cooling rack, they will be crisp and ready to eat in a minute or two.
You can trim them if you would like perfectly formed pizzelle, (I usually don't) and/or sprinkle them with a little powdered sugar if you like (I usually do).