For the decoration: roasted hazelnuts chips and / or more chocolate chips
Instructions
Preheat the oven to 190°C. In a large bowl, combine the flour, cocoa powder, baking soda, baking powder and salt.
In another bowl, mix the eggs and sugar, until the mix whitens. Incorporate the oil, sourd cream and vanilla extract, and mix again.
Pour the dry ingredients onto the liquid ingredients and mix just enough to incorporate the powders (the dough doesn't have to be smooth, lots of lumps should remain).
Line your muffin tin with paper cups and divide the dough between the 12 holes. Sprinkle with the hazelnut or chocolate chips.
Bake in the middle of the oven for 20 minutes (in conventional oven mode if possible). Let the muffins cool down for 10mn in their tin before turning them out on a cooling rack.
Notes
To get high-domed muffins like in Starbucks: before baking it let the dough rest 5 minutes in the muffin tin before baking. This prevent the dough from overflowing on the sides. Also prefer conventional heat over fanned heat, it helps the muffins to rise.
Recipe by Anne-Sophie Vidal - Fashion Cooking at https://www.fashioncooking.fr/2016/11/starbucks-chocolate-muffins/