Preheat the oven to 375°F., To make the crust: In a medium bowl, beat the butter at medium speed. Add the sugar, vanilla, and salt, and beat until blended. Scrape the bowl, then mix in the flour and nuts. Press this mixture into the bottom and about 1/2" up the sides of a 9" or 10" springform pan., Bake the crust for 12 to 15 minutes, until lightly browned. Remove from the oven and set aside to cool. Reduce the oven temperature to 325°F., For the filling: In a large bowl, beat the cream cheese and sugar at low speed until soft and no lumps remain, stopping to scrape the bowl once or twice. Add the eggs one at a time, mixing until each egg disappears before adding the next. Scrape the bowl and mix for 30 seconds more., Stir in the rum extract, vanilla, sour cream, heavy cream, and nutmeg. Mix just until the mixture is smooth., Pour the batter into the prepared pan, and bake for 45 to 50 minutes. The edges of the cake will look set and be light golden brown, and the middle should still jiggle when you nudge the pan., When the temperature of the cake 1" in from the edge reaches 165°F, turn the oven off, prop open the door, and let the cheesecake cool slowly in the oven for 1 hour. During this time the center will finish setting., After 1 hour, remove the pan from the oven and run a thin spatula around the edge to allow the cake to contract evenly as it cools. Chill for 2 hours (or overnight) before topping., For the topping: Stir together the sour cream, sugar, and vanilla; set aside. Whip the heavy cream until stiff peaks form, then fold into the sour cream mixture. Spread on top of the chilled cheesecake., To garnish: Mix the garnish ingredients, and sprinkle over the top of the cake. Refrigerate until ready to serve., Store any leftovers, well wrapped, in the refrigerator for up to four days.