1. With a sharp knife, remove the peel and skin from the orange. Working over a large bowl to catch the juice, cut the segments from their surrounding membranes. (Discard membranes, pith and skin.) Add pork, fennel, onion, oil, vinegar, salt and pepper to the bowl; toss to combine. Sprinkle with pepitas.

Tips:
Ingredient Note: Pepitas, olive-green-hulled pumpkin seeds, are commonly used in Mexican cooking. Find them in the bulk-foods section of natural-foods markets or Mexican grocers.

To toast seeds: Cook in a small dry skillet over medium-low heat, stirring constantly, until fragrant and lightly browned, 2 to 4 minutes.

MAKE AHEAD TIP: Cover and refrigerate for up to 1 day. Sprinkle with pepitas just before serving.