Pour 3/4 cup cold water into a large bowl and sprinkle the 4 tbsp gelatin over the top. Let it sit while you prepare the syrup.
Slightly heat the syrup:
In a medium saucepan, combine 1 cup maple syrup and 1/4 tsp salt. Heat gently just until warm to the touch—do not boil.
Combine syrup and gelatin:
Carefully pour the warm syrup into the bloomed gelatin while mixing on low speed, preferably in a stand mixer.
Whip to perfect fluffiness:
Increase speed to high and whip for 10–12 minutes—or until the mixture has doubled in size, is thick, glossy, and fluffy. Add 1 tsp vanilla extract near the end.
Set and cut:
Pour into a greased or parchment-lined pan, dust with powdered sugar or arrowroot powder, and let it set for 4 hours or overnight at room temperature. Cut into squares and toss with more powdered sugar to prevent sticking.
Notes
Let the marshmallows set completely at room temperature before refrigerating. If they aren’t fully set, the gelatin can become gummy and the texture won’t turn out properly.Gently heating the syrup is all you need—do not boil. This keeps the natural sweeteners from caramelizing and ensures a great texture.