Beat the eggs and sugar in a large bowl until the sugar is completely dissolved.
Add the lemon zest and pinch of salt.
Add the olive oil little by little, mixing well after each addition.
Add the milk little by little.
Sift the flour and baking powder and add to the bowl. Mix slowly with a rubber spatula until everything is homogenous. Do not overmix.
To achieve the spongy texture of a Spanish magdalena, you'll need to let the mix rest in the fridge. Cover the bowl with plastic wrap and leave in the fridge for 30 minutes.
Preheat the oven to 400°F (200°C)
Line muffin trays with muffin wrappers
Fill the muffin wrappers 2/3 of the way, and, if you'd like, sprinkle a pinch of sugar on top of each muffin
Bake for 15 to 20 minutes on the middle rack, don't open the oven until you think they're ready
Test with a toothpick in the middle of a muffin to make sure they're cooked through
Let your magdalenas rest for at least five minutes before enjoying!