For the muffins
Heat the oven to 200°C (180° fan) 400°F gas 6. Grease a 12 hole muffin tin.
Sift the flour, cocoa and baking powder into a mixing bowl. Stir in the sugar.
Whisk together the eggs and oil in a separate bowl until frothy, then slowly whisk in the milk.
Stir into the dry ingredients until just blended. Stir in the chocolate chips.
Spoon into the tins to half fill them. Place about 2 teaspoons of chocolate spread on top of each muffin, then cover with the rest of the muffin mixture. Bake for 15-20 minutes until risen and springy to the touch. Cool in the tins for 5 minutes then place on a wire rack to cool completely.
For the chocolate ganache
Bring the cream to a boil in a pan. Remove from the heat and stir in the chocolate until melted. Stir in the butter, stirring until the mixture is glossy. Chill for about 1 hour until thick.
Whisk the ganache with an electric whisk until increased in volume and thick. Spoon the ganache into a piping bag and pipe on top of the muffins. Place a cherry half on top of the ganache.