How to Make It
Preheat oven to 325°F with rack in middle position. Toss pepitas with 1/2 teaspoon oil. Spread evenly on a baking sheet and bake, stirring occasionally, until golden and toasted, 12 to 15 minutes. Remove from oven and immediately toss with coriander, cumin, cayenne, and ⅛ teaspoon salt. Let cool, about 10 minutes.
Gently toss together arugula, apple, lemon juice, pepper, and remaining 2 tablespoons oil and ¼ teaspoon salt in a large bowl. Arrange salad on serving plates. Sprinkle with pepitas.