The only warning I can give you is, don't burn your mouth when eating these straight from the oven, yeah they're that good.
100g Plain chocolate (about 55% Cocoa Solids)
280g Plain flour
200g Light brown sugar
1tsp Bicarbonate of soda
1 Medium egg
100ml Buttermilk or plain yoghurt
1tsp Vanilla extract
150g - 200g Plain chocolate chips
Preheat the oven to 180ºC/350ºF/Gas Mark 4, line a 12 hole muffin tray with paper cases. Place the butter and chocolate together in a small microwaveable bowl and melt on high in 30 second intervals, allow to cool slightly.
Place the dry ingredients into a large bowl, stir to combine. Whisk the egg, buttermilk, milk and vanilla together with a fork then add the melted chocolate.
Slowly add the wet to the dry ingredients until just combined. Fold in the chocolate chips.