Preheat oven to 300ºF. In a large bowl, whisk together egg yolks and sugar until the sugar has dissolved and the mixture is thick and pale yellow. Add cream and vanilla, and continue to whisk until well blended. Strain into a large bowl, skimming off any foam or bubbles.

Divide mixture among 6 ramekins or custard cups. Place in a water bath and bake until set around the edges, but still loose in the center, about 50 to 60 minutes. Remove from oven and leave in the water bath until cooled. Remove cups from water bath and chill for at least 2 hours, or up to 2 days. When ready to serve, sprinkle about 2 teaspoons of sugar over each custard. For best results, use a small, hand-held torch to melt sugar. If you don't have a torch, place under the broiler until sugar melts. Re-chill custards for a few minutes before serving.