Galette des Rois (Kings' Cake) | America's Test Kitchen

Ingredients

• 1 cup (4 ounces/113 grams) almond flour
• ½ cup (3½ ounces/99 grams) sugar
• 2 tablespoons all-purpose flour
• ¼ teaspoon table salt
• 6 tablespoons unsalted butter , cut into ½-inch pieces and softened
• 2 large eggs
• 1 teaspoon rum
• 2 sheets puff pastry , thawed
• 1 dried bean , whole almond, or trinket (optional)
• 1 large egg , lightly beaten with pinch table salt
• 1½ tablespoons sugar
• 1 tablespoon water
• ½ teaspoon corn syrup