Make sure the eggs are at room temperature and the butter is soft before you begin. Place the muffin cases in a muffin tray or directly on a baking tray and preheat the oven to 190°C (fan).

Add the butter to a mixing bowl and beat with a mixer fitted with beaters until soft and creamy. Add the muffin mix, eggs and water and mix on the lowest speed until combined. Then mix for 1 minute on medium speed, taking care not to overwhip or aerate the batter. If desired, fold chocolate pieces or blueberries into the batter. Divide the batter evenly among the muffin cases using two tablespoons or an ice cream scoop.

Place the tray slightly below the centre of the oven and bake the muffins for approximately 18 to 20 minutes until golden brown and cooked through. The muffins are done when they spring back lightly after pressing the top gently with your finger.