Sift the cornstarch and powdered sugar together. Grease well a 9x13 cake pan. Coat pan with sugar/cornstarch mixture
OPTION: Coat with crushed toasted almonds
Place 3/4 cup water in a small wide bowl. Sprinkle gelatin over water, stir, and allow to sit till needed
Add the granulated sugar, corn syrup, and 1/2 cup water into a small pot. Stir gently to combine and bring to a boil. Don't stir any further.
When syrup reaches 240, place the egg whites into the HotMixPro, with the butterfly, and process at speed 3, 95F, till soft peaks. When the syrup reaches 250 F slowly pour into the HotMixPro, running at speed 2. Break up the gelatin and add that as well. Adjust speed to 4 and process until marshmallow triples in volume and has become thick.
Add the vanilla extract.
OPTION: Substitute 1 tsp almond extract.
Pour marshmallow mixture into the prepared pan. Top with about a quarter cup of the cornstarch/sugar mixture.
OPTION: Instead of topping with sugar mixture, top with 1.5 cups toasted almonds.
OPTIONAL: Top with some caramel.
OPTIONAL: Coat with tempered chocolate