Step 1

Preheat the oven to 200C/400F/Gas Line a 12-hole muffin pan with muffin cases, and set aside.

Step 2

Whisk together the flour, cocoa powder, baking powder, and salt. Set aside.

Step 3

In a separate large bowl, whisk together the eggs and sugar until thick and lighter in colour. Add the buttermilk, oil, and vanilla, and whisk until combined.

Step 4

Add the dry ingredients in thirds and fold in until just combined - do not overmix. Fold in the chocolate chips. The mixture will be thick and somewhat lumpy.

Step 5

Divide the batter evenly between the 12 muffin cases, filling only half way. Spoon 1 teaspoon of Nutella into the centres, then top with the remaining batter.

Step 6

Bake for 15 - 20 minutes, or until a toothpick inserted just off centre (to avoid Nutella) comes out clean.

Step 7

Allow to cool for 5 - 10 minutes in the pan before transferring them to a wire rack to cool completely.