Almond Croissant French Toast with Almond Butter Syrup

Name: Almond Croissant French Toast with Almond Butter Syrup
Ingredients: 1 stick unsalted butter, cut in half; 4 tablespoons unsalted butter; 1/4 cup sliced almonds; 3/4 cup pure maple syrup; 1/4 teaspoon pure almond extract; 3 eggs; 3 egg yolks; 2 tablespoons pure cane sugar; 1 1/4 cups half-and-half; 1/4 teaspoon pure vanilla extract; Pinch sea salt; 4 fresh all-butter croissants, sliced crosswise partway through, opened and flattened; Confectioners' sugar, for garnish; Fresh mint leaves, for garnish