Preheat oven to 250 degrees F.
To a medium size mixing bowl, add pumpkin seeds,melted butter, brown sugar, sea salt, chili powder, and cumin; toss to coat.
Pour seeds evenly into a prepared 11x13 baking dish. Bake 90 minutes, stirring every 30 minutes.
Remove from oven, season with additional salt to taste, then serve.