Preheat the oven to 450 degrees . In a medium bowl, beat together the eggs and milk; stir in the flour, 1/2 teaspoon salt and 1 pinch pepper. Gently stir in the chives, then let stand at room temperature for 30 minutes.
Brush two 6-cup jumbo muffin pans with the oil (or use twelve 8-ounce ramekins set on a rimmed baking sheet). Transfer to the oven and let stand until hot, about 5 minutes.
Transfer the muffin pans to a heatproof work surface. Working quickly, add 1/4 cup batter to each cup, then bake until puffed and golden-brown, 15 to 17 minutes. Run a knife around each cup to loosen and serve immediately.