Preheat the oven to 300°F. In a medium-size mixing bowl, combine 3 cups of the pumpkin seeds, 2 tablespoons vegetable oil and 1 teaspoon salt; stir to coat well. Spread the seeds onto a baking sheet. Bake for 65 to 70 minutes or until lightly browned and crisp, stirring often to brown the seeds evenly. Cool to room temperature. To store, place in a tightly covered container (will keep for 1 week). Makes 3 cups.