Preheat the oven to 350 °F. Line 2 muffin trays with 14-16 liners.
To a large bowl, add the flour, cocoa, baking soda and powder, salt, espresso powder and chocolate chips. Whisk to combine.
Add the coconut oil to a microwave safe bowl and heat for 20-30 seconds in the microwave until melted. Whisk in the yogurt and sugar followed by the eggs and continue to stir until well combined.
Pour the wet mixture into the flour mixture and mix until just combined. Add the shredded zucchini and fold to combine.
Fill muffin liners ¾ full and bake in the oven for 18-20 minutes until a toothpick in the center comes out mostly clean or the centre of the muffins bounce back when pressed lightly.
Allow to cool in the tin for 5 minutes and then move to a wire rack to cool completely.
Notes
LeftoversStore leftover muffins in an airtight container at room temperature for up to 3 days or freeze for up to 3 months.