1. In a medium metal bowl soften gelatin in 1 1/2 tablespoons cold water for about two minutes.

2. Whisk in egg yolks and sugar and place bowl over a pan of gently simmering water.

3. Cook, whisking constantly, until mixture reaches 160 degrees. Remove from heat.

4. Transfer egg mixture to the bowl of a stand mixer fitted with a whisk and beat until cool and thickened, about 5 minutes.

5. Add pumpkin and spices and beat until combined.

6. Chill mixture until cool, but not set, about 1/2 hour.

7. When filling has chilled, whip cream to soft peaks and add vanilla.

8. Using a rubber spatula, add 1/3 of the whipped cream to pumpkin mixture and gently mix until well combined.

9. Gently fold in the remaining whipped cream.

10. Spoon or pipe into glasses and chill, uncovered, until firm, about 3 hours.

NOTE: Mousse can be stored, covered, in the refrigerator for up to one day.