2 deep 6- to 8-inch freezer-safe bowls, 4-inch round cookie cutter, 5-inch round cookie cutter, 7-inch round cookie cutter, pastry bag (optional), plastic deli container lid, kitchen torch, grill starter or lighter
For the base: Bake each box of spice cake according to the package instructions in parchment-lined half-sheet pans, jelly roll pans or rimmed cookie sheets. Let cool.
Line 2 deep 6- to 8-inch freezer-safe bowls with plastic wrap. Using a 4-inch round cookie cuter, cut out 2 circles of cake and place 1 in the bottom of each bowl. Layer about half a pint of softened pumpkin ice cream on top of each layer of cake. Using a 5-inch round cookie cutter, cut out 2 more circles of cake and place them on top of the pumpkin ice cream. Layer about half a pint of softened salted caramel ice cream on top of each layer of cake. Using a 7-inch cookie cutter cut out 2 more circles and layer them on top of the salted caramel ice cream. On one of the bowls layer the remaining pumpkin ice cream on top of the top layer of cake. (The second bowl should have its top layer as cake and not ice cream.) Freeze both bowls until completely solid, 4 hours up to overnight.
Unmold the cake and ice cream layers from the bowls and press the flat-edges together to make a ball.
For the crumb coating: Using 1 container of store bought vanilla frosting (or homemade vanilla buttercream) frost the entire outside of the ball until fully covered. If necessary pop the cake into the freezer if the ice cream starts to melt while frosting.
Place the remaining cake scraps into a food processor and pulse until coarsely ground. Coat the entire exterior with the crumbs and place back into the freezer until frozen solid, about 2 hours.
For the meringue: In the bowl of a stand mixer fitted with the whisk attachment, whisk together the confectioners' sugar and egg whites until combined. Place the bowl over a pot of simmering water and heat, whisking occasionally, until the mixture is very hot. Carefully transfer the contents of the bowl to the mixer and whisk on medium-high speed until fluffy and slightly cooled, about 4 minutes. Add the cinnamon, salt and food coloring to make pumpkin-orange and whisk on medium to combine.
For the decorations: Roll gum paste out and cut into the eyes, mouth, stem and vines and decorate the pumpkin, if using.
Remove the ice cream and cake ball from the freezer. Unmold the cake from the the bowls and remove the plastic wrap. Place the ball on a serving plate. Spread the meringue over the ball or transfer the meringue to a pastry bag and pipe it over the ball.
Make a comb to make the pumpkin grooves: Cut the outer hard ring of a plastic deli container lid off. Cut out the shape of "3" on one side of the lid (discard the cut out piece). In one motion, us the shaped lid to comb the meringue from the bottom to the top of the cake. Clean the excess meringue off of the comb and repeat until the pumpkin is fully grooved. (If desired, use a kitchen torch to slightly brown the meringue in the grooves to add dimension).
Decorate the pumpkin with with the gum paste eyes, mouth, stem, vines and leaves.
Return the pumpkin to the freezer until ready to serve.
To serve: Gently heat the whiskey in a small saucepan over a low flame or in the microwave in a heat-proof gravy boat or glass measuring cup until hot and almost boiling. Ignite the hot whisky with a grill starter or lighter and pour over the pumpkin. Cut into slices and serve.
Use extreme caution when igniting alcohol. Remove the pan from the heat source before adding the alcohol. Pour the alcohol into the pan and carefully ignite with a match or click lighter. Return the pan to the heat and gently swirl to reduce the flames.
Propane gas torches are highly flammable and should be kept away from heat, open flame and prolonged exposure to sunlight. They should be used only in well-ventilated areas. Follow torch manufacturer's instructions for use.