Preheat the oven to 350˚ F. Combine the coconut oil, agave, 1 tablespoon red pepper jelly, the lime juice, cayenne and a pinch of salt in a small saucepan over medium heat. Cook, stirring, until melted and combined, 1 to 2 minutes.
Combine the pepitas and sunflower seeds in a medium bowl; pour the coconut oil mixture over the seeds. Stir to combine. Line a baking sheet with parchment paper, then coat with cooking spray. Spread the seeds on the baking sheet and bake, stirring halfway through, until golden brown, about 10 minutes. Remove from the oven, sprinkle with the lime zest and toss to combine. Let cool, then break into smaller pieces.
Meanwhile, put the brie on a separate baking sheet and bake until hot and melted in the center, 7 to 10 minutes. Transfer to a serving dish; top with the remaining 1/4 cup red pepper jelly, the pepita granola and chopped cilantro. Serve with plantain chips.