Sprinkle gelatin over ½ cup (120ml) room temperature water and set aside to bloom.
Using a rolling pin or the bottom of a heavy pan, crush the palm sugar into small pieces. In a small sauce pot, combine the palm sugar with 1 cup (240ml) water and heat, stirring occasionally, just until sugar is dissolved. Remove from heat and stir in the gelatin mixture and tamarind concentrate. Add an additional 8 ounces (240g) ice by weight or 1 cup of ice water by volume to dilute and chill the popsicle base.
Divide evenly among 10 (3-fluid-ounce) popsicle molds and freeze until just beginning to firm, about 30 minutes. Insert popsicle sticks and continue freezing until completely solid, about 8 hours. To un-mold, dunk molds in hot tap water for a few seconds and jiggle sticks to release. Wrap individually in plastic and freeze for up to 3 weeks.
For the chili salt, in a small bowl combine the cayenne, sugar, salt, and malic acid. Dip the edge of each popsicle into the chili salt before serving.
