In a medium bowl slightly whisk 2 large eggs, add seasoning and 1 tbsp water. Melt 1/2 tbsp butter in a cast iron skillet over medium-high heat. When the foam dissipates, add the eggs and cook for 5-10 seconds, until the bottom is set. Using a fork, lift the edges of the egg mixture and let the uncooked mixture run under to cook. Keep repeating this until the omelet begins to set all over but is still quite soft. Sprinkle with the herbs and mushrooms.