Step 1: In a medium bowl, whisk together the eggs yolks, milk, and a pinch each of kosher salt and pepper until combined.
Step 2: In a large bowl using a handheld mixer, beat the egg whites until they hold stiff peaks, about 1 minute. Using a spatula, gently fold the egg whites into the yolk mixture until just combined. It is okay if the mixture is not completely smooth; just be careful not to deflate the whites.
Step 3: In a 10- to 12-inch skillet, melt 1 tablespoon of the butter over medium heat. Add the egg mixture and cook without moving until the top of the egg just begins to set, about 4 minutes. Add the artichokes, spinach, and Brie to one side of the omelet, cover the skillet, and cook for 2 to 3 minutes more, or until the cheese just begins to melt. Carefully fold over the empty side of the omelet to enclose the filling and cook for 1 minute more.
Step 4: Remove the pan from the heat and slide the omelet onto a plate.
Step 5: In a small saucepan, melt the remaining 2 tablespoons of butter with the honey over medium heat. Stir until melted and smooth. Remove the pan from the heat and stir in a pinch of flaky salt.
Step 6: Drizzle the omelet with the honey butter and top with blueberries.