Preheat your waffle iron.
Put the Egg White Protein, baking powder, onion powder, and dried thyme in a bowl and whisk together well.
Add the cold mashed potatoes and mix well. Then add the eggs and mix.
If using a mini waffle maker, spoon a scant 3 tablespoons of the mix onto the center of the lower plate, spread out quickly to the edges and close the lid.
Cook for 5 minutes (use a timer!), then carefully remove the waffle before repeating for the remaining waffles. You should not need to oil the waffle iron, but you may want to have some spray oil on hand, especially if your iron is old or if the nonstick coating has worn off.