Beat egg yolks, 4 tablespoons sugar and vanilla in a mixing bowl until thick and creamy.
Pour cream into a saucepan and stir over low heat until it almost comes to boil. Use a fine mesh infuser or a Tea Sac to infuse the Earl Grey de la Crème into the cream while it's heating. Remove the cream from heat immediately when it starts to simmer. Stir cream into the egg yolk mixture; beat until combined.
Pour cream mixture into the top of a double boiler. Stir over simmering water until mixture lightly coats the back of a spoon; approximately 3 minutes. Remove mixture from heat immediately and pour into 4 ramekins.
Bake in preheated oven for 30 minutes. Remove from oven and cool to room temperature. Refrigerate for 1 hour, or overnight.
Preheat oven to broil.
Sift 4 tbsp sugar evenly over custard. Place ramekins under broiler until sugar melts, about 2 minutes. Watch carefully so as not to burn.
Remove from heat and allow to cool. Refrigerate until custard is set again, about 3 hours.