Berry High-Protein Marshmallow Without Sugar

Prep your mat or parchment paper and get your piping bag with tip ready: you'll be working fast with agar-agar.

Thaw the berries and blitz them in a blender until smooth, then transfer to a saucepan over low heat.

Once it comes to a boil, add the agar-agar and sugar substitute, stir well, and simmer for about 4 minutes, stirring constantly.

While the syrup's cooking, whip your egg whites with citric acid until you get stiff peaks.

Pour the hot berry syrup into the whites in a thin stream while you keep whisking, then continue whisking for another 30 seconds or so.

Quickly transfer the mixture into your piping bag and pipe the marshmallows onto the mat or parchment.