Preparation

• Mix the buttermilk and salt together in a small bowl. Add the two pieces of hearts of palm, cover and refrigerate overnight.
• Remove the hearts of palm from the buttermilk; reserve the buttermilk.
• Split the vanilla bean and scrape the seeds into a medium saucepot. Add the bean pod, hearts of palm, cream and ½ cup sugar to the pot. Over medium-low heat, bring the mixture to just below a simmer, until it reaches about 190 degrees. Stir in the gelatin to dissolve. Add the reserved buttermilk.
• When the sugar and gelatin have dissolved, strain the mixture into a pourable container. Reserve the hearts of palm halves, letting them dry thoroughly. Pour the mixture evenly into 6-ounce panna cotta molds. Refrigerate at least 4 hours, ideally overnight.
• Meanwhile, candy the hearts of palm: Julienne the reserved hearts of palm. In a saucepan, bring ½ cup water, the remaining sugar and the hearts of palm to a gentle simmer over medium heat. Let simmer 10 to 20 minutes until the mixture is nearly caramelized.
• Pour the mixture on a sheet pan lined with wax paper and let cool and harden. Break apart.
• To serve, gently slide the panna cottas from their molds onto plates. Garnish with the candied hearts of palm.