Preheat oven to 300 degrees F. Line 2 baking sheets with parchment paper. Arrange racks in the oven so that you can put both baking sheets in if they won't both fit on one rack.
In a large bowl, combine oats, ground flax seed, coconut, sunflower seeds, walnuts, pecans, cinnamon and salt. Mix well.
In a small bowl or measuring cup, combine coconut oil, maple syrup and vanilla. Pour over dry ingredients and stir to combine.
Spread half of the mixture onto each prepared pan. Bake for 30-35 minutes until lightly browned - stir halfway through and reverse the pans if they are on 2 racks.
Allow to cool and then store in a tightly covered container.
Notes
Use any combination of chopped nuts, totalling 3 cups, in place of the sunflower seeds, walnuts and pecans. I use 2 cups oatmeal and 2 cups hemp hearts in place of all oatmeal, for a lower grain version.