Then mix like this

1. Preheat oven to 180C. Grease mini loaf trays or muffin trays.
2. Add butter to the bowl. Melt 3 minutes / 70C / Speed 2.
3. Place flour, sugar, eggs, milk, choc chips, cocoa powder, vanilla and a pinch of salt to the bowl. Speed 4 / 5 seconds to just combine.
4. Pour mixture into each muffin hole until 3/4 full. Bake for 20-30 minutes or until cooked through.
5. After 15 minutes, carefully remove bars from the tray and cool on a wire rack.

Or cook like this

1. Preheat oven to 180C. Grease mini loaf trays or muffin trays.
2. Add butter to a microwave safe bowl. Melt in the microwave for 30 seconds on medium heat.
3. Place flour, sugar, eggs, milk, choc chips, cocoa powder, vanilla and a pinch of salt to a large bowl with the butter.
4. Pour mixture into each muffin hole until 3/4 full. Bake for 20-30 minutes or until cooked through.
5. After 15 minutes, carefully remove bars from the tray and cool on a wire rack.