Preheat the oven to 350ºF. Line a baking sheet with parchment paper.
In a bowl, beat together the nut butter, syrup, flax egg, sugar, and vanilla. Once smooth, stir in the flour, oats, chocolate chips, baking soda, and salt.
Scoop the dough onto the baking sheet. Gently flatten and place in the oven. Bake for 10 - 12 minutes until golden brown. Remove from the oven and sprinkle with flaked salt if desired. Allow the cookies to cool for a few minutes before transferring them to a cooling rack.