Special equipment: parchment paper
Preheat the oven to 450 degrees F. Cut four large pieces of parchment paper into 14-inch hearts by folding the paper in half and cutting half of a heart shape (like you would to make a paper valentine). Set aside.
In a medium bowl, toss together the fennel, kale, 2 tablespoons of the oil and 1 teaspoon of the salt. Open the hearts so the tip is facing toward you. Place two slices of orange on the right side of each heart, close to the center. Divide the vegetable mixture on top of each set of orange slices.
Place a piece of fish on top of each mound and season each fillet with 1/8 teaspoon of the remaining salt and 1/8 teaspoon fennel pollen. Drizzle each piece of fish with 1/2 tablespoon of the remaining oil. Top each fillet with one of the remaining orange slices. Close the heart so it is now just a half of a heart and rotate it so the mound is facing you and the tip is away from you. Begin to make small folds, each one overlapping the last, around the edge of the package to seal the edges. When you get to the tip, fold the point under the packet. Place the packets on a baking sheet and cook until the packet is slightly brown and puffed, 12 to 15 minutes. Using scissors or a small pairing knife, cut open the top of the each packet carefully, as the escaping steam will be hot. Serve in the parchment packets for easy clean up.