In a small bowl, stir together gelatin and ¼ cup water; let stand until soft, about 5 minutes.
In the top of a double boiler, whisk together egg yolks, maple syrup, and remaining ½ cup water. Cook over simmering water, whisking constantly, until mixture registers 160° on a candy thermometer. Remove from heat, and whisk in gelatin mixture until melted.
In the bowl of a stand mixer fitted with the whisk attachment, beat yolk mixture at medium-high speed until mixture is cooled and thickened, about 10 minutes.
In a large bowl, beat cream with a mixer at high speed until stiff peaks form. Fold whipped cream into cooled egg yolk mixture. Cover and refrigerate for at least 4 hours before serving. Spoon or pipe mixture into individual serving dishes. Sprinkle with Candied Walnuts, and garnish with maple syrup, if desired.
CANDIED WALNUTS
In a large skillet, stir together walnuts, sugar, butter, and cinnamon. Cook over medium heat, stirring constantly, until butter and sugar are melted and walnuts are shiny. Spoon onto a piece of parchment paper in a single layer, and let cool completely. Store in airtight containers for up to 2 weeks.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/maple-mousse-candied-walnuts-recipe/