In a bowl, whisk together the eggs, milk or cream, salt, and pepper until well combined.

Heat a non-stick skillet over medium-low heat and add the butter.

Once the butter is melted and foamy, pour in the egg mixture.

Allow the eggs to sit for a few moments, then gently stir with a spatula, pushing the eggs from the edges to the center.

Continue to cook slowly, stirring occasionally, until the eggs are softly set and fluffy.

If using, add in chopped spinach, diced peppers, or cheese just before the eggs are fully cooked.

Remove from heat and serve immediately.