Preheat the waffle iron to medium or medium-high. A too-hot iron can burn the exterior before the inside cooks. Lightly brush both plates with melted butter.

Choose your base: If using store-bought croissant dough, unroll and keep the triangles chilled. If using pre-baked croissants, split them in half horizontally so they heat evenly and compress nicely.

Optional egg wash and sugar: For extra shine and a delicate caramelized finish, whisk 1 egg with a splash of water. Brush the tops lightly and sprinkle a pinch of sugar. This step is best for sweet versions.

Layer for height (if using dough): Stack two dough triangles together, offset slightly so the points don’t align perfectly. This helps keep flaky layers distinct without bulging in one spot. Gently press to adhere, but don’t flatten too much.

Season the dough lightly: A small pinch of salt and a drop of vanilla on the surface can elevate flavor. If making savory, skip vanilla and add a tiny sprinkle of black pepper.

Cook in the waffle iron: Place the dough stack (or split croissant halves) onto the center of the iron. Close gently—you want the plates to compress the dough but not squeeze butter out entirely. Cook for 4–6 minutes, depending on your iron, until deeply golden and crisp.

Check doneness carefully: Lift the lid slowly at the 4-minute mark. If it resists, give it another minute. You’re looking for even browning and a dry, crisp surface that springs back slightly when tapped.

Rest on a rack: Transfer the waffle to a wire rack for 1 minute to let steam escape. This keeps the exterior crisp instead of soggy.

Repeat with remaining dough or croissant halves, re-buttering the iron as needed.

Serve warm with your chosen toppings. For savory versions, add a slice of cheese while the waffle is still hot so it melts into the ridges.