Clean pumpkin - Remove the top of the pumpkin using a sharp knife and by cutting around the stem. Use a spoon to scrape the pulp and seeds out of the inside of the pumpkin. Toss the pulp and seeds into a bowl.
Preheat oven - Preheat to 350 degrees F and line a large rimmed baking sheet with foil or parchment.
Clean seeds - Separate the pulp from the seeds. In order to rinse the seeds thoroughly, put the seeds in a colander and rinse with cold water.
Prepare seeds - Spread the seeds in an even single layer onto the prepared pan. Dry pumpkin seeds by pressing paper towels over them to dab most of the water off.
Add seasoning - Drizzle melted butter (or olive oil) over the top and sprinkle with salt.
Bake - Bake in the preheated for 24 minutes, stirring once halfway through, until they are golden brown. Remove from the oven and enjoy immediately!