Dry the bread: Dry out slices of wheat and white bread in a 200°F (93°C) oven for about 30 minutes.
Prepare cereal coating: Blitz Captain Crunch cereal in a food processor until finely crushed to create a crunchy coating.
Make custard: In a bowl, whisk together 3 eggs, 1 cup whole milk, a splash of vanilla paste, 1/2 teaspoon cinnamon, freshly grated nutmeg, a big pinch of kosher salt, and 3 tablespoons white sugar.
Soak bread in custard: Thoroughly soak the cooled, dried bread slices in the custard mixture.
Coat bread with cereal: Dip the custard-soaked bread slices into the crushed Captain Crunch cereal, coating them evenly.
Fry the French toast: Heat butter in a pan over medium heat until foaming. Fry the coated bread slices for 2 to 3 minutes per side until golden and crunchy.
Keep warm: Place cooked French toast on a rack set in a rimmed baking sheet and keep warm in the oven until all slices are done.
Serve: Serve the Captain Crunch French toast with a dainty pad of butter and a generous pour of maple syrup.