- 3 tablespoons unsalted butter
- 1/2 medium sweet apple, such as Fuji, Braeburn, or Pink Lady, peeled, cored, and thinly sliced
- 6 large eggs
- 4 teaspoons whole milk
- 1/2 teaspoon kosher salt
- 1/4 teaspoon freshly ground black pepper
- 2 tablespoons crumbled blue cheese, such as Stilton
- 2 bacon slices, cooked and crumbled
- Melt 1 tablespoon of the butter in an 8-inch nonstick frying pan over medium heat until foaming. Add the apples and cook, stirring occasionally, until softened, about 4 minutes. Transfer to a small heatproof bowl and set aside. Wipe out the pan with a paper towel; set the pan aside.
- Whisk the eggs, milk, salt, and pepper in a large bowl until pale yellow and the egg yolks and whites are evenly combined. Set 2 serving plates aside.
- Melt 1 tablespoon of the butter in the reserved frying pan over medium heat until foaming. Add half of the egg mixture (about 3/4 cup) to the pan and stir constantly with a rubber spatula, moving the eggs around until they form small curds, about 2 to 3 minutes.
- Gently shake the pan and use the spatula to spread the egg mixture evenly across the pan—the top of the eggs should have a creamy consistency. Sprinkle all over with half of the blue cheese. Spoon half of the apples and sprinkle half of the bacon down the middle third of the egg mixture.
- Remove the pan from heat. Using the spatula, fold a third of the omelet over and onto itself, making sure to fold it over the filling.
- Gently push the folded side of the omelet toward the edge of the pan. Tilt the pan over one of the serving plates and roll the omelet onto the plate, seam side down.
- Repeat with the remaining tablespoon of butter, eggs, cheese, apples, and bacon. Serve immediately.