Add egg yolks to a small saucepan; whisk until lemon yellow and slightly thick, about 1 minute. Whisk in lemon juice.
Add 2 tablespoons cold butter, and place over very low heat. Whisk constantly while butter is melting, and continue whisking until thick enough to see the pan between strokes. Remove pan from heat, and beat in 1 tablespoon cold butter. Repeat. Whisk in melted butter a little bit at a time. Season with salt and white pepper to taste.