Instructions

1. In a big mixing bowl, mix the powdered sugar and the cornstarch until well combined. Set aside.
2. Grease an 8×8-inch baking dish and dust the bottom and the sides of it with 1/4 C of powdered sugar and cornstarch mixture.
3. Add aquafaba, vanilla extract, and cream of tartar into a bowl of a stand mixer. Beat at high speed until hard peaks are formed. Set aside.
4. In a medium saucepan, combine water and agar agar powder.  Bring the mixture to a boil, stirring continuously. Let it boil, stirring occasionally, for 2-3 minutes or until it thickens.
5. Add sugar and a pinch of salt and keep boiling for 2 more minutes, stirring occasionally.
6. Turn on the stand mixer to low and slowly pour the agar agar mixture into the bowl while gradually increasing the speed. Beat it for 5-8 minutes.
7. Quickly transfer the marshmallow fluff to the powdered baking dish. Spread it evenly with a spatula. Dust the surface with another 1/4 C of powdered sugar and cornstarch mixture.
8. Let it cool down at room temperature for 4-6 hours or overnight.
9. Preheat oven to 65°C (150°F).
10. When marshmallows are set, run the spatula around the sides of the dish.
11. Sprinkle powdered sugar mixture on a flat surface and flip the marshmallows out of the pan. Cut the marshmallows into cubes of the desired size. Roll all the sides in the remaining powdered sugar and cornstarch mixture.
12. Transfer your vegan marshmallows onto a lined baking sheet. Switch the oven off and place the marshmallows inside. Let them dry in the oven for 1 hour.
13. Store the vegan marshmallows in an air-tight container for up to 2 weeks.