Heat oven to 300°. Bring cream and vanilla bean with seeds to a simmer in a 2-qt. saucepan over medium-high heat. Remove from heat and let sit for 30 minutes; discard vanilla bean. In a bowl, whisk sugar and yolks until smooth. Slowly pour in cream mixture, whisking until smooth; set aside.
Place a paper towel in the bottom of a 9″ x 13″ baking pan, and place six 6-oz. ramekins inside pan. Divide custard among ramekins. Pour boiling water into pan to come halfway up outsides of ramekins. Bake until custards are set but still slightly loose in center, about 35 minutes. Transfer ramekins to a wire rack; cool. Chill until firm, at least 4 hours.
Dab any condensation off surface of custards with a paper towel. Sprinkle turbinado sugar evenly over surface of each custard. Guide the flame of a blowtorch back and forth over surface until sugar caramelizes; let sit briefly until sugar hardens.