Add egg yolks and sugar into a bowl. Whisk them until it comes together. Set aside.
Add whipping cream, milk and agar agar powder into a saucepan. Warm it up on low heat. Whisk for 30 seconds until the agar agar powder dissolves.
Add Earl Grey tea bags and turn up the heat to medium-low. Use a spatula to stir the mixture for 1 minute until the fragrance and colour from the tea emits.
#Tip: Do not worry if the tea bags break as we will sieve the mixture before filling the tart shells.
Turn fire off, continue to stir the mixture for 30 seconds to prevent it from setting.
Pour Earl Grey mixture into the egg yolk mixture gradually. Whisk quickly to prevent the eggs from cooking.
Cook mixtures on medium heat for 1 minute until it boils.
Sieve mixture before filling the tart shells. Transfer into refrigerator and chill for 20 minutes.
Assemble and ready to serve
After custard has set, add tapioca balls on top with a spoon.