Creating these delightful Chocolate Spinach Muffins can be straightforward if you follow these simple steps:

1. Preheat the Oven: Preheat your oven to 350°F (175°C). Line a muffin pan with paper liners or grease the cups.
2. Mix Dry Ingredients: In a large bowl, whisk together the whole wheat flour, all-purpose flour, cocoa powder, baking soda, baking powder, and salt until well combined.
3. Combine Sugars: In a separate bowl, mix the granulated sugar and brown sugar until they are well blended.
4. Mix Wet Ingredients: In another bowl, whisk together the vegetable oil, eggs, vanilla extract, milk, and blended spinach until well incorporated.
5. Combine Mixtures: Gradually add the wet ingredients to the dry ingredients, gently folding until just combined. Take care not to overmix.
6. Add Chocolate Chips: If desired, gently fold in the chocolate chips for an extra chocolatey touch.
7. Scoop Batter: Using a spoon, carefully scoop the batter into the prepared muffin pan, filling each cup about ¾ full.
8. Bake: Place the muffin pan in the preheated oven and bake for 20-25 minutes, or until a toothpick inserted in the center comes out clean.
9. Cool: Once baked, remove from the oven and let the muffins cool in the pan for a few minutes before transferring them to a wire rack to cool completely.

Following these steps will result in irresistible Chocolate Spinach Muffins that are ready to be enjoyed!