Step 1

Preheat the oven to 180C/160Fan/350F/Gas mark Line a 12 hole muffin tin with muffin liners.

Step 2

Melt the 50g dark chocolate in a heatproof bowl set over a pan of barely simmering water. Once the chocolate has melted, remove from the heat and set aside.

Step 3

Combine the plain flour, salt, baking powder, bicarbonate of soda and cocoa powder in a large bowl and mix with a fork to comine the ingredients. Stir in the chocolate chips, keeping a few back to sprinkle over the top of the muffins.

Step 4

In a large jug or bowl, whisk together the sugar, sour cream or buttermilk, oil, vanila extract and egg until well combined. Stir in the cooled melted chocolate. Pour the wet mixture over the dry ingredients and quickly but lightly stir until you have a lumpy-ish batter. Don't try and beat all the lumps out - a lumpy batter makes the best muffins.

Step 5

Spoon the batter into the muffin liners, about two thirds full. Sprinkle with the reserved chocolate chips and bake for 20-22 minutes or until well risen.