One medium sized pumpkin
Salt
Olive Oil

Preheat oven to 400°F. Cut open the pumpkin and use a strong metal spoon to scoop out the insides. Separate the seeds from the stringy core. Rinse the seeds.   

In a small saucepan, add the seeds to water, about 2 cups of water to every half cup of seeds. Add a half tablespoon of salt for every cup of water (more if you like your seeds saltier). Bring to a boil. Let simmer for 10 minutes. Remove from heat and drain.

Spread about a tablespoon of olive oil over the bottom of a roasting pan. Spread the seeds out over the roasting pan, all in one layer. Bake on the top rack until the seeds begin to brown, 10-20 minutes. When browned to your satisfaction, remove from the oven and let the pan cool on a rack. Let the seeds cool all the way down before eating. Either crack to remove the inner seed (a lot of work and in my opinion, unnecessary) or eat whole.