Preheat the oven to 300 degrees F. Line a baking sheet with parchment paper.
In a large bowl, beat the egg whites and water until frothy. In a small bowl, combine the sugar, cinnamon, allspice, cumin, salt and cayenne. Stir the sugar mixture into the egg whites, then add the pepitas and pecans. Toss until the nuts are completely coated.
Evenly spread the nuts on the prepared baking sheet. Bake 20 to 30 minutes, until crispy. Let cool completely. Store in an airtight container.