Scoop out the seeds from the pumpkin and separate them from the pulp. Rinse the seeds thoroughly under cold running water to remove any remaining pulp.
Dry the cleaned seeds completely. Spread them in a single layer on a clean kitchen towel or paper towels and let them air dry for at least an hour, or preferably overnight.
Preheat oven to 325°F (160°C).
Place the dried seeds in a bowl, drizzle with oil, and toss to coat. Sprinkle with salt, pepper, and garlic powder, and toss again to ensure even coating.
Line a baking sheet with parchment paper. Spread the seasoned seeds in a single layer on the prepared baking sheet.
Roast for 20-25 minutes, flipping halfway through, until golden brown and crispy.
Allow the roasted seeds to cool completely on the baking sheet before storing in an airtight container.
