Mix the corn starch into the plant milk 1 Tbsp at a time to make a slurry.
In a medium bowl, whisk together the coconut custard and ube condensed milk. Stir in a few drops of purple food dye if desired to enhance the color. Mix in the slurry.
Place a small sauce pot over medium heat. Add the ube custard to the pot. Whisk constantly until you achieve a rolling boil then remove from heat.
Divide the custard between the tart shells, then chill for 1 hour to set.
Top each tart with 2-3 tsp of sugar. Brulee the tops with a kitchen torch. You can also use this methodin the oven if you don't have a torch.
Serve right away.
Recipe by Carrots and Flowers at https://www.carrotsandflowers.com/vegan-ube-creme-brulee-tarts/