56 grams (¼ cup) water
15 grams (2 tablespoons) powdered gelatin (about 2 envelopes)
¼ teaspoon salt
Cornstarch or arrowroot
Pan spray or butter for pan
340 grams (2 cups) Grade B maple syrup
Combine the gelatin with the water and salt in the bowl of a stand mixer. Fit the mixer with the whisk attachment.
Grease an 8-inch square pan and then dust generously and evenly with sifted cornstarch or arrowroot.
In a large, heavy saucepan (at least 3½ quarts) heat the maple syrup to 240° over medium heat. Be careful: As the syrup heats it can boil up and over the top of your pan if it’s not large enough. Remove from heat.
Turn on mixer to medium-low and slowly and carefully pour the hot maple syrup into the gelatin. Increase mixer speed to medium-high. Whip until light and marshmallow-y. Scrape into prepared pan (an oiled scraper or hands make this easier. Let sit overnight until firm. Unmold from pan and cut into squares.