Preheat oven to 180 degrees C, or 350 degrees F.
Add the flour, baking powder, baking soda, cocoa powder and monkfruit sweetener to a large bowl and stir with a whisk to combine, making sure any lumps are broken up and smoothed out.
In a separate bowl, whisk the egg. Add the vanilla and milk and whisk together again. Add the melted and cooled oil and whisk vigorously.
In the bowl with the dry ingredients, make a well in the centre. Pour in the wet ingredients to the dry ingredients, along with the chocolate chips. Use a spatula to gently mix together. Its important to not over stir the batter as it will make the muffins tough.
Using either a silicone muffin mold, or paper inserts into a metal muffin tin, spoon the muffin mixture evenly across 12 regular sized muffin cases, filling each one to the top .
Bake for 22 minutes in oven at 180 degrees C, or 350 degrees F. To test if they are cooked, insert a cake skewer or toothpick into the centre. If it comes out clean, they are cooked.
Let muffins cool for 5 to 10 minutes in the muffin tray, then gently remove them and set on a wire rack to cool to room temperature.
Once at room temperature, store in an air tight container for 2 days Alternatively you can freeze them for upto 2 months.