Bought a cheap French waffle iron. But, the mix for the batter was expensive. So, tried a few recipes. Most involved egg separation & folding whipped egg white back into the batter. Could be improved with a bit of malted milk powder.
you want the batter moderately thick, anyway not to runny. Based on the measurements above it’s never runny, but sometimes thick. If so, add a splash of buttermilk and mix by a couple stirs. You don’t need a mechanical mixer, a few swift stirs with a large spoon should incorporate the ingredients well enough.
Preheat the waffle iron. Either brush with butter or use vegetable spray. Follow directions for your waffle iron. The batter will keep for a day or two in the fridge if covered. I have a cheap ($20) French waffle iron I got online. It’s the flip kind with a light that goes on to tell me when the waffle is done.