For the blown-sugar eyeball: Boil the Isomalt and water together; add the gel.
Bring to 320 degrees F on a candy thermometer.
Pour the mixture onto a silicone baking mat and blow into 1-inch spheres (about 30).
For the creme brulee: Mix the cream, mascarpone, milk, egg yolk and sugar together with the hand mixer.
Fill up 1.4-ounce containers with the mixture and cook in a 200-degree oven for 1 hour.
Cool down the creme brulee.
Mix the xanthan gum and the cooled creme brulee together with a hand mixer.
Transfer to a piping bag and fill up the sugar spheres.