Preheat your oven to 400°F and line a 12-cup muffin tin with paper liners.

In a large mixing bowl, whisk together the eggs and sugar until well combined and slightly pale.

Gradually pour in the vegetable oil and milk, continuing to whisk until the mixture is smooth.

Stir in the vanilla extract.

In a separate bowl, sift together the all-purpose flour, baking powder, and salt.

Gently fold the dry ingredients into the wet mixture until just combined, being careful not to overmix.

Evenly distribute the batter among the prepared muffin cups, filling each about three-quarters full.

Bake in the preheated oven for about 20 minutes, or until the tops are golden and a toothpick inserted into the center of a mantecada comes out clean.

Allow the mantecadas to cool in the pan for 5 minutes before transferring them to a wire rack to cool completely.