Preheat the oven to 275°F (135°C) with a rack in the center. Line a sheet pan with parchment paper.
Mix the oats, pecans, coconut, sunflower seeds, salt, and cinnamon in a large bowl.
Stir together the melted coconut oil, maple syrup, and vanilla. Pour over the dry ingredients and mix until evenly coated.
Press the mixture into one even layer on the prepared pan. Bake at 275°F for 1 hour.
Rotate the pan, increase the oven to 300°F (148°C), and bake for 20–25 minutes, until golden, dry, and fragrant. Cool completely before breaking into clusters and storing.