Inspired by Jacques Genin's to-die-for mango passion caramels, I tweaked the apple cider caramel recipe from Smitten Kitchen to make these exotic, chewy delights. The vanilla bean tempers the bright tang of the passion fruit and also provides the subtlest little crackle. —Joy Huang | The Cooking of Joy
passion fruit pulp (the easiest to find is the frozen Goya brand, sometimes with the frozen fruits, sometimes with the frozen ethnic foods)
Line the bottom and sides of an 8- inch straight- sided square metal baking pan with 2 long sheets of crisscrossed parchment. Set it aside.
Make a lengthwise slit down the side of the vanilla bean and open it up. Scrape out the seeds and add it to a small saucepan along with the cream and butter. Heat on medium just until the butter is melted and turn off the flame. Gently stir to break up the vanilla seed clusters. Let steep for 10-15 minutes.
Meanwhile, boil the passion fruit pulp in a 3- to- 4- quart saucepan over high heat until it is reduced in volume by half. Stir occasionally, making sure that it doesn't burn.
Once you are finished reducing the passion fruit pulp, remove it from the heat and stir in the sugars and vanilla cream mixture. Return the pot to medium heat with a candy thermometer attached to the side, and let it boil until the thermometer reads 252°F.
Immediately remove caramel from heat and pour caramel into the prepared pan. Let it sit until cool and firm—about 2 hours, though it goes faster in the fridge.
Once caramel is firm, use your parchment paper sling to transfer the block to a cutting board. Use a well-oiled knife, oiling it after each cut, to cut the caramel into batons about 2" long and 3/8" wide. Wrap each one in waxed paper, twisting the sides to close.