Preheat the oven to 350° F. Line a 9x13” baking dish with parchment leaving about an inch overhang and set aside.
In the bowl of a food processor, combine 3/4 cups rolled oats and flaxseed. Pulse until oats are coarsely ground and resemble the consistency of bread crumbs. Transfer the mixture to a large bowl and add the remaining 1 cup whole rolled oats, cinnamon, and salt.
Place chopped walnuts on a small baking sheet and toast for 5-7 minutes, until nutty and fragrant. In the last 2-3 minutes of toasting, add the coconut chips. Remove from the oven when everything is lightly browned and let cool while you mix the wet ingredients.
In a medium bowl, combined melted coconut oil, maple syrup, brown sugar, vanilla extract, and nut butters. Whisk until smooth and homogenous.
Pour combined wet ingredients into the dry ingredients and fold with a rubber spatula until well mixed and a crumbly batter has formed. Fold in the walnuts, toasted coconut, and chocolate.
Pour the mixture into the prepared pan and use a rubber spatula or your hand to press down into an even layer. Bake for 25-30 minutes, rotating the pan halfway through the baking time, until golden brown. Remove from the oven, sprinkle with flaky salt, and let cool in the pan for at least an hour. (The longer you let them cool, the more likely they will hold together). If you want to speed this up, when the pan has cooled mostly, you can transfer it to the refrigerator.
When you are ready to slice, grab the parchment paper sides and gently lift the bars out of the pan. Slice into even squares and share with a friend!