Preheat the oven to 400 degrees F. Grease muffin tin well or line with paper liners.
In a medium bowl, whisk together the spelt flour, cocoa powder, salt, baking powder and baking soda.
In a blender combine melted coconut oil, buttermilk and coconut sugar, eggs, lemon zest and spinach and blend to create a "green smoothie".
Add the green smoothie to the dry ingredients and mix until just combined. Don't over mix muffin batter. Stir in chocolate chips.
If you have time, allow the mixture to sit in the fridge for one hour as this will give the muffins a better rise. If time doesn't allow, move ahead to the next step.
Distribute batter into the prepared muffin wells. If desired, top muffins with a few chocolate chips. Bake in a preheated oven at 400 degrees F for 5-6 minutes and then lower the oven temperature to 350 degrees F. (No need to open the oven door.)
Continue to bake for 13-15 minutes. Total baking time is approximately 20 minutes. The muffins are ready when a cake tester comes out clean.