Heat oven to 325°F.
In large skillet roast the teff grain on medium high heat until it starts making sizzling/popping sounds. Allow the teff to pop for about 45 seconds once popping begins. Stir regularly throughout roasting process, especially once popping starts. Set roasted teff aside until called for below
In a large bowl, combine the nut butter, syrup , cinnamon and vanilla. Stir well.
Add the remaining ingredients, except for the eggs, and mix until everything is evenly distributed and all the dry ingredients have been moistened. Let sit in bowl for about 15-20 minutes.
Mix in eggs or egg substitute.
Cover a rimmed baking sheet with parchment paper and spray lightly with cooking spray.
Pour the granola bar mixture onto the greased paper and press evenly across the pan.
Bake for 20-25 minutes.
Allow the bars to cool completely in the pan before cutting into bars.
Refrigerate leftovers for up to a week or freeze, individually wrapped in plastic, for up to a month.