1. Combine egg yolks, lemon juice, cayenne, salt and pepper in a heavy saucepan 2. Whisk together until thoroughly blended 3. Add the butter and set the pan over medium heat 4. Whisk constantly so as the butter melts, it is blended into the egg-yolk base 5. Regulate the heat so butter melts gradually 6. When butter is melted and blended into the egg-yolk base, continue whisking until the sauce just thickens to a creamy consistency 7. Taste the sauce and add more lemon juice, salt and pepper if needed Makes about 1 1/4 cups