Yields 16 large marshmallows or 64 small.
Special equipment: a candy thermometer
In a small bowl, combine the raspberry powder, confectioners’ sugar and cornstarch. Coat an 8-inch square or 9-inch square baking dish with cooking spray and dust the bottom and sides with half of the confectioners’ sugar mixture. Pour any excess mixture back into the bowl.
In the bowl of a stand mixer fitted with a whisk attachment, combine 1/2 cup water, the vanilla extract and almond extract. Sprinkle the gelatin over the liquid.
In a small saucepan, stir together the granulated sugar, corn syrup, salt and the remaining 1/4 cup of water. Clip on a candy thermometer. Heat the mixture over medium-high heat until it reaches 240 degrees F and then immediately remove from the heat and transfer to the mixer.
Turn the mixer on low and drizzle the sugar mixture in a slow and steady stream down the side of the bowl. Once the entire mixture is in, gradually increase the speed to high and mix until lukewarm and fluffy, 7 to 10 minutes. While the mixer is running, grease a rubber spatula and have that standing by the mixer, as well as the prepared pan.
Using your greased spatula, immediately scrape the mixture into your pan and spread it out evenly as best you can with the spatula. Dust the top with about half of the remaining confectioners’ sugar mixture and then, if needed, you can use your hands to further flatten and even out the mixture. Let sit for 1 hour. Cut into squares and then dust the edges of the squares with the remaining confectioners’ sugar mixture.