Pour heavy cream into a saucepot. Turn heat to medium. When cream reaches a boil, reduce heat and bring cream to a gentle simmer. Whisking frequently, simmer gently for about 10 minutes or until cream becomes thick. Add lemon juice and whisk well. Turn heat off. Keep the pan on the burner and whisk in chunks of cold butter, several pieces at a time, whisking as the heat from the pan and cream warms the butter and the sauce emulsifies. Once all the butter has been incorporated into sauce consistency, season with salt and pepper.