1 1/2 teaspoons unflavored gelatin
1 1/2 Tablespoons cold water
1 1/2 cups chilled heavy whipping cream
1 1/2 cups of mascarpone cheese (room temperature)
3/4 cup sugar
5 large egg yolks
1 1/2 cups canned pure pumpkin
1 1/4 teaspoons vanilla extract
3/4 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/4 teaspoon ground nutmeg
1/4 teaspoon salt
1/8 teaspoon ground allspice
In a medium metal bowl sprinkle gelatin over cold water to soften 1 minute. Whisk in yolks and sugar and set bowl over a saucepan of simmering water (not boiling). Cook egg mixture, whisking constantly, until an instant-read thermometer inserted 2 inches into mixture registers 160°F. Remove bowl from pan and with an electric mixer beat egg mixture until cool and thickened, about 5 minutes (mixture will be very sticky).
In a separate bowl , Beat cream and vanilla until it holds stiff peaks, reserve in refrigerator
In a large bowl, whip mascarpone until smooth, then blend pumpkin, cinnamon, ginger, nutmeg, salt and allspice.
Fold in egg mixture gently but thoroughly, then fold in whipped cream.
Transfer mousse mixture into a large pastry bag fitted with a large plain tip or transfer into a clean bowl. Mousse can be piped in or spooned in to desired serving pieces, refrigerate uncovered, until firm, approximately 3 hours before serving. Can be made a day ahead, cover loosely if refrigerated for more than 3 hours.