Truffled Egg Salad: Peel eggs and dice into 1/4-inch pieces. Combine mayonnaise, oil, salt, lemon juice and vinegar. Fold in eggs. Refrigerate until ready to use.
Mushroom Mousse: Heat oil in heavy-gauge pot on medium heat. Add mushrooms, onions, garlic, salt and thyme; cover. Sweat until vegetables are tender, stirring occasionally. Add 8 oz. stock; bring to simmer. Cover, remove from heat, and let stand 30 min. Puree mixture, then strain into bowl; discard solids.
Sprinkle gelatin over remaining 3 oz. stock in small bowl. Let stand 5 min. Heat bowl over simmering water until all gelatin is dissolved and mixture reaches 90°F. Stir gelatin mixture into mushroom mixture. Cool in an ice bath.
Gently fold whipped cream into mushroom mixture. Refrigerate until ready to serve.
Crispy Prosciutto: Meanwhile, arrange prosciutto in single layer on parchment paper-lined sheet pan. Bake in 350°F standard oven (or 300°F convection oven) 11 to 13 min. or until crisp. Cool at room temperature until ready to use.
When ready to serve, plate 2 oz. Mushroom Mousse with 2.5 oz. of Truffled Egg Salad in front of the Mousse and 0.20 oz. of Crispy Prosciutto to the right of the Egg Salad. Serve with 2 packets of RITZ Crackers.