Preheat the oven to 300°F. Spray a 9×13 sheet tray with deep sides with cooking spray.
Place a large sheet tray on the bottom rack of the oven.
In a large bowl, add the eggs, cream, butter, salt, pepper, and chives.
7 large eggs, 1/3 cup heavy cream, 2 tablespoons unsalted butter, 1/2 teaspoon kosher salt, 1/4 teaspoon black pepper, 2 tablespoons minced chives
Whip with an electric hand mixer for 2 minutes until frothy.
Pour egg mixture into the prepared sheet tray.
Pour 2 cups of hot tap water into the sheet tray in the oven.
Place the sheet pan with the egg mixture on the middle rack and bake for 20-25 minutes, until the eggs are set and start to lightly brown. The eggs will puff as they bake.
Allow to cool slightly, the eggs will settled down. Slice and serve.
Notes
Whisk Eggs Well: Use an electric hand mixer to whip the eggs for a fluffy texture.
Preheat the Pan: Preheat your sheet pan in the oven for a few minutes before pouring in the egg mixture for even cooking.
Use Parchment Paper: Line the sheet pan with parchment paper for easy removal and cleanup.
Add Toppings Before Baking: Add your favorite toppings right before baking so they get perfectly cooked into the omelet.
Check Doneness: Bake until the eggs are set and lightly browned on top. You can test with a toothpick in the center.
Cool Before Slicing: Let the omelet cool slightly before slicing to help it set and make it easier to serve.