Preheat the oven to 325°F (163°C). Line a large cookie sheet with parchment paper or a silicone baking mat. Set aside.

Mix oats, peanuts, and cocoa powder together in a large bowl. Melt peanut butter, honey, and coconut oil together in a medium bowl and stir until smooth. Mix in the vanilla extract. Pour over oats and mix until all oats are moistened.

Bake for 30 minutes, stirring and flipping every 10 minutes. Remove from oven and, if adding chocolate chips, sprinkle the granola with them while it is still warm. Stir. The chocolate chips will melt, creating larger clusters of granola. Allow to cool at room temperature for at least 30 minutes. The air will help the granola get crunchy.