Scoop out the pumpkin seeds and place them in a colander under running water. Separate the bits of remaining pulp and discard. Drain well.
Transfer the pumpkin seeds into a large pot. Add water and salt and bring to a boil over medium heat. Reduce heat to low and simmer for 10 minutes. Drain well.
Pour the drained pumpkin seeds into a bowl. Add olive oil and garlic powder. Stir to coat.
Spread the coated pumpkin seeds out in a large rimmed baking sheet. Bake at 375˚F for 25-30 minutes, stirring and turning every 5 minutes, until the seeds are golden and crunchy.