Banana Tower

To prepare the phyllo discs: Put the butter in a sprayer. Preheat the oven to 350 F. Line 2 baking sheets with parchment paper and spray lightly with butter. Wipe off excess. Spread one phyllo sheet on a work surface and lightly spray with melted butter. Sprinkle with hazelnuts and confectioner’s sugar. Spray lightly with butter and top with a second phyllo sheet. Repeat, ending with the last phyllo sheet. Spray with butter and dust with confectioner’s sugar. Cut into four 5-inch circles and place on the prepared pans. Bake 10 to 12 minutes, until golden brown. Remove and set aside to cool.

To make the mousse: Dissolve the gelatin in 1/4 cup of cool water. Put the white chocolate in a heatproof bowl. Put the half-and-half in a heavy saucepan and bring to a boil. Remove from heat immediately and pour over the chocolate. Let stand for 30 seconds, then start stirring them together from the center outwards with a spatula. Cover with plastic wrap and chill in the refrigerator for 30 minutes. Fold in the gelatin, then fold in the whipped cream.

Place four 5-inch ring molds on a baking sheet and fill with the mousse. Cover the molds and the remaining mousse in the bowl and refrigerate until firmly set, or freeze.

To make the caramel sauce: Place the sugar and water in a medium, heavy saucepan. Bring to a simmer over medium heat, swirling occasionally. Cover the pan, raise heat to medium high, and cook for 2 minutes, or until the liquid gives off large, thick bubbles. Remove the cover and cook, swirling the syrup, until it turns golden brown.

Remove the pan from heat and stir in the butter with a wooden spoon. Add the hot cream, being careful of spatters. Stir until incorporated, then add the rum. Return the pan to low heat and stir constantly until any lumps have melted and the mixture is smooth. Keep warm.

To prepare the tops: Cut the baby bananas into thin discs. Place 4 phyllo discs on a work surface and spray with butter. Overlapping the slices, circle each top with banana slices, working toward the center until the entire disc is covered. Spray with butter and sprinkle with confectioner’s sugar. Using a torch, salamander, or broiler, brown the top of each disc.

To caramelize the bananas: Cut each banana into thin slices on the bias. Put the banana slices, butter, sugar, and rum into a medium saute pan and place over medium-high heat. Cook until the mixture turns a golden brown, stirring gently with a wooden spoon while they cook. Set aside.

To assemble: Place a phyllo disc in the center of each serving plate. Unmold the mousses and place one on each phyllo disc. Top each with a second phyllo disc. Spoon some of the caramelized banana slices over the discs. Put a scoop of mousse from the bowl on top of the banana slices. Place the browned tops on top of the scoops and press together gently. Place remaining banana slices around each plate, and drizzle with caramel sauce. Dust the plates with confectioner’s sugar.