Waffles (Crispy Outside, Fluffy Inside)

Method

1. 1Preheat your oven to 100°C (212°F) and set a wire rack on a baking sheet inside — this is where finished waffles will wait without steaming themselves soft. Preheat your waffle iron to medium-high heat and give it the full warm-up time your model calls for; a properly heated iron is the single biggest factor in achieving crisp waffles. You'll know it's ready once you pour in the batter and close the lid — if steam isn't rising within about 10 seconds, give the iron another minute or two before you try again.
2. 2Whisk the flour, cornstarch, baking powder, baking soda, sugar, and salt together in a large bowl. In a separate bowl, combine the buttermilk, egg yolks (not the whites — set those aside), melted butter, and vanilla extract. Pour the wet ingredients into the dry and stir with a spatula until just combined — you want a few lumps remaining. Overmixing develops gluten, which turns waffles tough and chewy instead of tender. Let the batter rest for 5 minutes while the iron finishes heating — this gives the cornstarch time to hydrate and the baking powder time to start producing gas.
3. 3Once the batter has rested, whip the egg whites in a clean bowl with a whisk or hand mixer until they hold stiff peaks: lift the whisk and the tip of the peak stands straight up without drooping. Gently fold the whites into the batter using a large spatula, cutting down through the center and sweeping along the bottom. You want to keep as much air as possible trapped in the batter. A few streaks of white are fine; the goal is volume, not uniformity. Start baking straight away, before the foam has time to settle.
4. 4Ladle the batter onto the center of the hot iron, using about 120–150 ml per waffle depending on your iron size. Close the lid and do not open it for at least 3 minutes. Steam will pour out at first — when the steam slows to a thin wisp, the waffle is close to done. Cook until deep golden brown, about 3–5 minutes total.
5. 5Transfer each finished waffle directly to the wire rack in the oven — never stack them on a plate, which traps steam and makes the bottom soggy within a minute. The oven keeps them warm and the wire rack lets air circulate on both sides, preserving the crunch. Repeat with the remaining batter. Serve with maple syrup, fresh berries, whipped cream, or a dusting of powdered sugar — but serve quickly, because these waffles are at their absolute best within 5 minutes of coming off the iron.