Preheat the oven: Preheat your oven to 325°F (165°C). Line a large baking sheet with parchment paper.
Mix the wet ingredients: In a large bowl, combine the pumpkin puree, maple syrup, melted oil, vanilla extract, pumpkin pie spice, cinnamon, and salt. Stir until smooth and well combined.
Add the dry ingredients: Add the rolled oats, chopped nuts, and pumpkin seeds to the pumpkin mixture. Stir thoroughly until the oats and other ingredients are evenly coated.
Spread the granola: Transfer the mixture to the prepared baking sheet. Spread it into an even layer and gently press it down with a spatula if you want larger crunchy clusters.
Bake: Bake for 30–40 minutes, stirring gently once or twice during baking. Continue baking until the granola is golden brown and smells toasted.
Cool completely: Remove the baking sheet from the oven and let the granola cool completely on the pan. It will become crisp as it cools.
Add mix-ins: Once completely cool, stir in dried cranberries, chocolate chips, or shredded coconut if desired.
Serve and store: Enjoy immediately or transfer the cooled granola to an airtight container. Store at room temperature in a cool, dry place.