Preheat the oven to 350 degrees F. Line a rimmed baking sheet with a piece of parchment paper and set aside.
In a large bowl, mix together the oats, oil, syrup and salt. Toss well to coat evenly. Spread the mixture on the prepared baking sheet and bake for 30 minutes, stirring halfway through. Remove the baking sheet and stir in the almonds and walnuts. Bake, stirring halfway through to brown evenly, an additional 25 to 30 minutes. Let cool completely, then stir in the chocolate chunks.
The granola will keep in an airtight container for up to 2 weeks.