Preheat the oven to 250°F (120°C). Spread pumpkin seeds in a single layer on a baking sheet. Toast for 45 minutes, stirring occasionally, until dry and toasted. Larger seeds may take longer.

In a large bowl, stir together 2 tablespoons of white sugar, salt, and pumpkin pie spice. Set aside.

Heat the oil in a large skillet over medium-high heat. Add the pumpkin seeds and sprinkle the remaining sugar over them. Stir with a wooden spoon until the sugar melts, about 45 seconds.

Pour seeds into the bowl with the spiced sugar and stir until coated. Allow to cool before serving.