Preheat your oven to 200°F (95°C) to keep the cooked waffles warm and crisp.
Preheat your waffle maker according to the manufacturer’s instructions.
In a large bowl, whisk together the flour, baking powder, sugar, and cornstarch.
In a separate bowl, whisk together the eggs, Greek yogurt, vanilla extract, and milk until smooth.
Make a well in the center of the dry ingredients and pour in the wet mixture.
Gently whisk until just combined — do not overmix.
Let the batter rest for a few minutes while the waffle maker finishes heating.
Pour batter into the waffle maker (usually 1/3 to 1/2 cup, depending on your machine).
Close the lid and cook for 3–5 minutes, or until golden brown and crisp.
Transfer waffles directly to the oven rack to stay warm and crisp — avoid stacking.
Serve immediately with your favorite toppings like fruit, whipped cream, or syrup.