Line a standard size muffin tin with liners, set aside.
In a large mixing bowl or the bowl of a stand mixer, combine the sugar and oil. Beat on high for 2 minutes.
Combine the cocoa and the hot water in a small bowl, whisk until a smooth paste forms. Add to the sugar and oil, beat for 1 minute.
Add the eggs and vanilla, mix until combined.
In a separate mixing bowl, whisk together the flour, baking powder and salt.
Gradually alternate adding the dry ingredients and the Greek yogurt to the large mixing bowl. DO NOT OVER-MIX. Fold in 1 cup of the chocolate chips.
Using a large scoop, fill each liner. Sprinkle the remaining ⅓ cup of chocolate chips on top and gently press into the batter.
Place in the oven to bake for 7 minutes, then reduce the heat to 350F/180C/Gas 4. and continue baking for 10-12 more minutes. The cracks should look slightly moist and the edges should be firm.
Remove from oven and allow to cool in the pan for 5 minutes before transferring to a wire rack to cool completely.
Recipe by at https://laurasglutenfreekitchen.com/2017/11/gluten-free-double-chocolate-muffins/