Preheat oven to 350.
Line an 8x8 baking dish with parchment paper (oil the inside of the dish so the parchment paper sticks).
Make flax egg by whisking together the flax and water in a small bowl, and setting it aside to thicken.
In a medium bowl, mix together the remaining ingredients for the shortbread layer, and fold in the flax egg. The mixture will be crumbly, but that's ok
Transfer the contents to the baking dish, and use your fingers to press everything down into the dish, as evenly as possible.
Bake for 10 minutes.
While the base is in the oven, make the topping.
Place a sauce pan on the stove over medium heat.
Add coconut oil, maple syrup, nut butter, and coconut sugar, stirring frequently so that everything begins to melt.
Bring to a boil for 1-2 min, then reduce heat to low.
Mix in the coconut milk and pecans. Make sure to coat everything well.
Transfer contents to baking dish, making an even layer on top.
Sprinkle chocolate chips evenly across the top.
Bake for 33-35 minutes.
Let cool completely before slicing into 12 squares.
Store in the refrigerator in an air right container for up to one week.