With a large mixing bowl, beat the egg, butter and buttermilk together. Then add your pancake mix, and whisk together until completely combined.
With a separate bowl, now beat the egg whites, along with some lemon juice, until you have some stiff peaks.
Next, gently fold the egg whites into your pancake mixture, and heat up a skillet with a medium to high temperature.
Then, put ¼ cup of your prepared batter into the skillet, and cook for 1 minute.
Next, flip the pancakes and cook for another minute. Serve up warm.