Preheat oven to 325 degrees F
Combine heavy cream and vanilla bean paste in a saucepan over medium heat. Stirring continuously, bring just to a boil and immediately remove from heat. Allow to rest for about 10 minutes while preparing other ingredients.
In a separate bowl, beat together egg yolks, sugar, and salt until the mixture is pale yellow and creamy, about 3 minutes.
Temper the egg yolk mixture; slowly drizzle ½ cup of warm cream into the egg yolk mixture while beating. Slowly add the remainder of the warm cream while beating the egg yolks. Mix in orange and lime zests.
Place a kitchen towel at the bottom of a 9” by 13” baking dish, and place ramekins on top of the towel. Bring water to a boil (using a kettle, if you have one).
Pour cream mixture directly into ramekins. Pour water into the pan beside the ramekins, making a water bath.
Carefully place water bath into your preheated oven and bake for 45-60 minutes. The finished dessert should be just set; the center may slightly jiggle, but it should not appear watery.
Using tongs or a hot pad, carefully remove ramekins from water bath and allow them to cool on a wire rack for 30 minutes minutes before placing them in the refrigerator.
Immediately before serving, sprinkle each ramekin with approximately 1 tablespoon of sugar - just enough so that there is a thin, even coat of sugar across the top of each ramekin.
Use a blowtorch to caramelize the sugar on each ramekin. If you don’t have a blowtorch, broil briefly on high, until ramekins are caramelized. Watch closely!