Preheat the oven to 350°F and grease a 12-count muffin tin with baking spray or line with parchment muffin liners. I highly recommend a silicone muffin pan.
In a large bowl whisk together the coconut oil, yogurt, maple syrup, eggs and vanilla extract. Once all combined, mix in the grated zucchini.
Next, in a separate large bowl, whisk together the flour, baking powder, baking soda and salt.
Add the dry ingredients to the wet ingredients and fold with a rubber spatula until well combined. Mix in the chocolate chips. The batter should be super thick.
Scoop ¼ cup batter into each muffin cavity, so each muffin is only filled ¾ of the way. If the muffin cavity is overfilled, the muffin will overflow. Press 4-5 chocolate chips into the top of each muffin. You should end up with a bit of extra batter that can be baked into 2-3 extra muffins.
Optionally, sprinkle the top of each muffin with coarse sugar.
Bake muffins for 23-25 minutes or until a toothpick inserted into the center comes out clean.
Allow the muffins to cool for 15 minutes before removing them from the pan onto a wire rack to cool completely.