Add the eggs, milk, flour and salt to a blender. Blend on high until completely smooth, then allow the batter to rest for 30 minutes.
Preheat the oven to 425 degrees F. Place a 12-cup muffin tin in the oven over a baking sheet and allow the pan to preheat while the oven is preheating.
After 20 minutes, remove the muffin tin from the oven and evenly pour the fat amongst the 12 cups (about 1 teaspoon of fat in each cup). Place the muffin tin back in the oven for 1 to 2 minutes to allow the fat to heat up.
Remove the baking sheet from the oven and carefully fill each cup a third of the way with the batter. Immediately place the baking sheet back in the oven and bake until golden brown and puffed, about 15 minutes. Serve while still warm.