How to Make It
Preheat the oven to 350°. Spread the almonds on a baking sheet and toast, for about 10 minutes, or until golden. Let cool; rub them between your hands until finely crushed.
In a small bowl, whisk together the cornstarch and confectioners' sugar. Using a pastry brush, lightly butter the bottom and sides of a 13-by-9-by-2-inch baking pan. Dust the pan with the cornstarch mixture. Evenly coat the bottom of the pan with 2/3 cup of the crushed almonds.
In a small bowl, sprinkle the gelatin over the juice; make sure the gelatin granules are evenly moistened. Put the whites in the large bowl of a standing electric mixer.
In a small heavy saucepan, stir together the granulated sugar, corn syrup and 1/2 cup of water. Bring the mixture to a boil over high heat, washing down the sides of the pan occasionally with a wet pastry brush. Insert a candy thermometer (be sure the bulb is completely submerged).
When the sugar syrup reaches 230°, begin beating the egg whites at medium-high speed. When the whites are foamy, add the salt and continue beating them until the sugar syrup reaches 245°. Remove the sugar syrup from the heat and quickly whisk in the softened gelatin until completely dissolved.
Beat the sugar syrup into the egg whites in a slow stream at high speed. Add the vanilla, and beat the whites until just cool, about 5 minutes. Using a large rubber spatula, fold in the orange zest.
Spread the meringue in the prepared pan and smooth the surface. Let stand uncovered in a cool dry place until set, at least 2 hours.
Sprinkle a work surface with the remaining crushed almonds. Run a knife around the edge of the pan to loosen the marshmallow. Turn out the marshmallow onto the nuts. Quarter the rectangle. Cut each quarter into 12 even pieces. Roll each piece in the nuts until completely coated. Set the marshmallows on a rack to dry for 2 to 3 hours before serving.
Make the recipe above with these changes: Omit the nuts. Increase the amount of cornstarch and confectioners' sugar to 1/4 cup each. Substitute lemon juice and zest for the orange juice and zest. Use 1 tablespoon of the cornstarch mixture to dust the pan and the remainder for rolling the marshmallows.
Make the recipe above with these changes: Substitute 2 cups unsweetened shredded coconut for the almonds in Step 1, and toast for 5 minutes, or until golden; let cool completely. In Step 2, substitute 2/3 cup of the coconut for the almonds. In Step 3, substitute cold water for the orange juice. In Step 6, add 1 teaspoon pure almond extract along with the vanilla and omit the orange zest. In Step 8, substitute the remaining coconut for the almonds.
Make the recipe above with these changes: Substitute 4 ounces semisweet chocolate for the almonds; grate the chocolate on the coarse side of a grater. In Step 2, dust the buttered pan with 1 teaspoon cornstarch mixed with 1 teaspoon confectioners' sugar and 1 teaspoon unsweetened cocoa powder. Evenly cover the bottom of the pan with 2/3 cup of the grated chocolate. In Step 3, substitute cold water for the orange juice. In Step 4, substitute dark corn syrup for light. In Step 6, substitute 2 tablespoons unsweetened cocoa powder for the orange zest. In step 8, substitute the remaining grated chocolate for the almonds.