Serve sabayon with fresh berries or topped with whole roasted chestnuts. Chocolate Straws make an elegant garnish.
Prepare a large ice bath, and set aside. Fill a medium saucepan with 2 inches water. Set over medium heat, and bring to simmer.
In a large stainless-steel bowl, whisk together egg yolks, salt, and sugar until very pale. Add Muscat; whisk to combine.
Place bowl over a pan of simmering water, and whisk until mixture has thickened and has tripled in volume, 8 to 10 minutes. Remove mixture from heat, and immediately transfer to ice bath. Whisk until chilled.
In a large chilled bowl, whip cream until soft peaks form. Add lemon juice, and fold the whipped cream into the chilled sabayon. Serve immediately.