After you rinse and pat dry the pumpkin seeds, you’ll roast them in the oven, then toss them with butter, sugar, salt, and a bit of cinnamon. In a pinch, you can toast pumpkin seeds in the microwave instead by heating them in a single layer on a glass baking dish or pie plate. Microwave pumpkin seeds for about 2 minutes and stir. Heat again for 2 to 3 minutes, stirring after each minute, until the seeds are lightly browned and crunchy.