Chocolate Cremeaux: Warm corn syrup in small saucepan on medium heat. Whisk in egg yolks until well blended. Remove from heat.
Bring cream and milk to boil in separate heavy saucepan on medium heat. Temper in corn syrup mixture. Cook on medium heat until mixture reaches 180°F, stirring constantly.
Place chocolate in large bowl. Strain warm cream mixture over chocolate; let stand 1 min. Stir from center out until mixture is completely emulsified.
Arrange 18 narrow dessert glasses (5 or 6-oz.) at an angle in hotel pan (see Tip). Fill each glass with 2 oz. chocolate mixture so that it is 1/2-inch from the top edge of the higher side. Refrigerate glasses until mixture is set.
Passion Fruit Mousse: Bloom gelatin in enough cold water to cover. Squeeze out as much water as possible. Place sheets in large bowl.
Meanwhile, heat egg yolks, passion fruit puree and sugar in heavy saucepan on medium heat until mixture reaches 180°F, stirring constantly. Pour through strainer over gelatin in bowl. Stir until gelatin is completely dissolved. Cool to room temperature over an ice water bath. Fold in whipped cream in 3 additions.
Spoon 2 oz. Passion Fruit Mousse over chocolate in each glass. Mixture will be about 1/4-inch from top of glass. Refrigerate until set.
Brownie Brittle: Sift powdered sugar, flour, cocoa, cornstarch, baking powder and salt into medium bowl. Mix oil, water, egg whites and vanilla in separate bowl until blended. Add liquid mixture to flour mixture; mix until well blended.
Spread mixture onto 2 half-sheet pans to within 1-inch of edges. Sprinkle each pan with 1-1/2 oz. OREO Pieces.
Bake in 350°F convection oven 25 min. or until crisp. (Brittle will crisp more as it cools). While Brittle is still warm, use pizza cutter to cut long strips about 3/4-inch wide. Cut each strip diagonally into 3 pieces. Cool completely. Store in airtight container at room temperature until ready to use.
For Each Serving: Top each chilled glass with 1/2 oz. of the OREO Small Pieces and 2 Brownie Brittle pieces.