Crown this rich and decadent chocolate dessert tart with whipped cream, kumquat slices, and chocolate shavings.
Combine almonds and brown sugar in a bowl. Place a portion at a time into a food processor bowl or blender container; cover and process or blend until nuts are finely ground. Transfer to mixing bowl. Stir in flour. Add melted butter, stirring until well combined. Press mixture onto bottom and 1 inch up sides of a 9-inch tart pan with removable bottom or a 9-inch springform pan. Bake in a 325 degree F oven about 20 minutes or until golden and firm to the touch. Cool crust on a wire rack.
Heat whipping cream in a small saucepan to simmering. Remove from heat; whisk in semisweet chocolate until smooth. Whisk in liqueur, if desired. Cool about 30 minutes or until filling begins to thicken but is still pourable. Spread marmalade over bottom of crust. Pour chocolate filling over marmalade. Cover and chill about 2 hours or up to 24 hours.
To garnish tart, if desired, pipe whipped cream along edges. Arrange kumquat slices on top of the piped cream. Sprinkle chocolate shavings over the center of the tart and along the edges. Makes 10 to 12 servings.