Preheat oven to 300 degrees then coat baking sheet with cooking spray. Remove seeds from cavity of the pumpkins then remove as much of the fibrous strands from the seeds as possible. Place seeds along with salted water into a large saucepan then bring to a simmer over medium heat.

Let pumpkin seeds simmer for about 10 minutes, drain water then pat seeds dry with a paper towel or lint-free kitchen towel. Place seeds in a small mixing bowl, drizzle with oil of your choice then sprinkle with a little bit of desired salt and spices.

Spread pumpkin seeds in a single layer on prepared baking sheet then bake for about 40–45 minutes, stirring frequently until the seeds are lightly browned and dry.