Tiramisu with Dulce de Leche Atop

To make the cake: Preheat the oven to 350 F. Butter 2 baking sheet pans. Beat the egg yolks with half of the sugar until light yellow in color. In a separate bowl, using clean beaters, beat the egg whites with the remaining sugar until firm peaks form. Fold the flour and egg yolks into the meringue with a spatula in three additions, alternating the two ingredients. Place in a pastry bag fitted with a large plain tip and pipe in lines which touch each other to fill in the pans, or, spread in the prepared pans to cover. Bake about 7 minutes, until the top firms and springs back slightly when touched. Remove from the oven and let cool. Dust heavily with confectioner’s sugar.

To prepare the cream: Beat the egg yolks and sugar together until light yellow in color. Gradually beat in the Mascarpone cheese. In a separate bowl with clean beaters, beat the heavy cream until soft peaks form. Fold in half the dulce de leche, reserving the remainder for assembly later. Fold a large spoonful of the cream mixture into the cheese mixture to lighten it, then gently fold the cheese mixture into the cream.

Cut sixteen 4-inch circles from the cooled cake. Place eight 4-inch diameter rings which are at least 4 inches tall on a baking sheet. Press one cake circle into the bottom of each ring. Combine the coffee and Amaretto and spoon over these cake circles to soak them. Spoon cream on the cake circles. Place a dollop of dulce de leche on top of the cream in each, using all the reserved dulce de leche. Split the remaining cake circles in half crosswise. Press one split half into each ring and spoon on more of the coffee-Amaretto liquid. Cover with a second layer of cream. Place one of the remaining split tops on top of each ring. Refrigerate at least 3 hours.

To make the sugar garnishes: Preheat the oven to 400 F. Line a heavy baking sheet with a silicone mat. In a small, heavy saucepan, combine the sugar, hot water, and cream of tartar. Insert a candy thermometer into the syrup and heat until the mixture reaches 310°F, just before it begins to turn an amber color. Pour the hot syrup onto the mat and spread it out fairly thin with a spatula; it is not necessary to spread it to cover the entire mat. Place in the oven for 2 to 3 minutes, until the sugar is bubbly. Remove and let stand until it is cool enough to handle. Loosen with a spatula, then lift and place on a piece of marble or steel or other surface where it can quickly cool. When completely cooled, crack into 4- to 6-inch pieces.

To prepare the sauce: Combine the ingredients in a heavy saucepan and heat over medium heat. Blend with a spatula until the ingredients are mixed, then whisk gently together to combine. Remove and keep warm.

To serve: Put the sauce in a squeeze bottle and draw diagonal lines in the bottom of eight dessert plates. Take the sheet of tiramisús out of the refrigerator and dust the tiramisús with cocoa powder. Gently warm a ring by wrapping for about 30 seconds in a towel dipped in very warm water and wrung out dry. Place in the center of one of the prepared plates and lift off the ring. Repeat with remaining tiramisús. Stand a sugar garnish in the top of each tiramisú. Garnish each with a sprig of mint.