Mix all the dry ingredients in a large bowl (flour, cacao powder, salt, baking powder, and baking soda).
2 1/2 cups all-purpose flour , 1/2 cup cacao powder, 1 tsp baking soda (bicarbonate of soda), 1/2 tsp sea salt, 2 tsp baking powder
In a separate bowl, cream the melted butter and sugars together until fluffy and light in color.
1/2 cup granulated sugar (I used unrefined), 1/2 cup melted butter, 1/2 cup light soft brown sugar
Add in the vanilla extract and orange extract.
1 tsp vanilla extract, 1 tsp orange extract
Mix in the two eggs.
2 eggs
Add the sourdough starter to the mixture.
1/3 cup sourdough discard or active starter
Add the orange zest and cardamom powder.
zest from 1 orange, 1 tsp ground cardamom
Mix in the milk. If the mixture looks a bit curdled at this stage do not worry about it. It will become smooth again at the end.
1 cup whole milk
Gradually add the dry ingredients to the wet mixture. Do not overmix.
Chop the chocolate into small chunks. Reserve some chocolate to shave on top of the muffins before baking.
Add the chocolate chunks to the batter. Fold them with a spatula instead of mixing.
1 1/4 cup chocolate chunks (milk or dark)
Leave the muffin batter to rest for 30 minutes. This will give some time for the leavening agents to activate and interact with each other.
Preheat the oven to 375°F (190°C) while resting the batter.
Prepare your muffin tray with the muffin paper cups.
Pour the muffin batter in the paper cups. All the way up but don't overfill.
Sprinkle some chocolate shavings on top.
Bake for about 30 minutes at 375°F (190°C). Insert a toothpick in the middle of a muffin to check if they are done. The toothpick should come out clean, without residue of raw dough on it.
Let them cool off in the muffin tray for 10 minutes.
Take them out and place them on a wire rack to completely cool.
Serve and enjoy!