Lucume Mousse

To make the lucume puree: In a heavy saucepan, combine the sugar and water and heat over medium-high heat until the sugar is completely melted and the mixture comes to a boil, about 3 minutes. Remove from heat and let cool completely.

Pull the skin off the lucumes and pull the flesh apart, putting it into the bowl of a food processor or blender. Add 1/2 cup of the simple syrup to the fruit; the remainder may be stored in a jar in the refrigerator for other use, and will keep up to 3 weeks. Puree. Alternatively, you may mash the fruit and syrup together in a bowl with a fork. Set aside.

To make the mousse: Bring some water to a simmer in a deep saucepan. Place the egg yolks in a stainless bowl which will fit over the pan without touching the water. Place the bowl over the simmering water and begin to whisk vigorously. Continue whisking until the eggs are thick enough to form a ribbon when the whisk is lifted. Remove the bowl from the heat and place in a bowl of ice. Continue whisking until the eggs have cooled; the mixture will thicken slightly.

In a small bowl or cup, dissolve the gelatin in the cool water.

Put the egg whites in the bowl of an electric mixer. Put the 3/4 cup of sugar, 1/4 cup of water, and lemon juice in a heavy saucepan over medium-high heat and stir until dissolved; stop stirring when the mixture comes to a boil. Let the mixture continue to heat, measuring the temperature with a thermometer; the target temperature is 239 F. When the syrup reaches 220 F, begin whisking the egg whites vigorously by hand. When the whites are foamy, whisk in the remaining tablespoon of sugar. Begin using the electric mixer, beating until stiff peaks form. Continuing to beat, slowly pour in the hot sugar mixture, which by now should have reached its target temperature of 239 F. Continue beating after all the sugar has been added until the meringue -- now called an Italian meringue -- has cooled to room temperature. The meringue will be very shiny, with firm peaks.

Fold the lucume puree into the cooled egg yolks. Fold a spoonful of meringue into the lucume mixture, then begin folding the lightened lucume mixture into the meringue along with the gelatin, working gently and using five additions to complete the process.

Beat the cream to soft peaks. Gently fold the whipped cream into the mousse to finish it.

To prepare the garnishes: Slice the lucumes into thin discs. Remove the rind from the oranges and cut the sections away in one piece from the white membrane, making supremes. Slice the apple into thin rings; remove the cores and toss the apple slices with the lemon juice.

To serve: Put the mousse in a pastry bag fitted with no tip, or a very large plain tip. Pipe the mousse into pretty serving glasses. Stand lucume slices in the top of each. Place the glasses on glass or other serving plates and surround with slices of apple, suprêmes of orange, and a selection of grapes. Garnish each with a mint leaf.