Preheat oven to 350.
In a medium bowl, stir together the almond flour, maple syrup, tahini, and collagen (if using).
Refrigerate dough for 30 min, then add egg/flax egg and baking soda.
Mix to incorporate well.
Fold in chocolate chips and marshmallows.
Line 8x8 baking dish with parchment paper (greasing inside so paper sticks).
Pour contents inside the dish and use a spatula to press down so everything is even.
Add a few extra chocolate chips and marshmallows to the top.
Bake 20-22 minutes. Note, this is longer than the cookie recipe because it's in bar form and it's thick.
Remove from oven after it's done and let cool before slicing into squares.