The sourdough version of one of the most typical Spanish muffins
Whisk the eggs and sugar until fluffy and light in color.
Add the starter and break down the blob a little (do it manually if you use your stand mixer, or the starter will curl up the whist attachment)
Add the heavy cream and the oil and whisk everything until it's combined.
Sift the flour and the baking powder and add the mixture to the wet ingredients in 2 or 3 times to avoid flour flying everywhere.
Mix the flour just to incorporate it. If you want to let the batter rest, now it's the time. Cover it with film and keep it in the fridge up to 12h. If you don't want to wait, preheat your oven at 350F.
When the oven is ready, line a cupcake pan and fill the cups about 3/4 of the way full, sprinkle with sugar in the center (about 1/2 tsp or so).
Bake the magdalenas until they're golden brown and let them rest in the pan for a few minutes.
Transfer the magdalenas to a cooling rack and let them cool down to room temperature.
* Use a weak all-purpose flour, if it has a high protein content mix it 50/50 with cake flour or your magdalenas will turn out a bit dry.
** You can use eggs straight from the fridge, especially if you are going to let the batter rest for a while in the fridge.