For Crust: HEAT oven to 375°F. Combine flour and brown sugar in medium bowl. Stir in butter with fork until evenly moistened. Stir in macadamias. Press evenly in 9-inch tart pan. Bake 10 minutes or until light brown. Cool completely on wire rack.
For Filling: COMBINE sugar and cornstarch in 2-quart saucepan. Whisk in cream and lime juice until smooth. Bring to a boil over medium-high heat stirring often. Boil 2 minutes, stirring constantly. Remove from heat. Stir in butter until melted. Cool to room temperature. Pour into crust.
For Topping: BEAT cream, powdered sugar and vanilla in small bowl with electric mixer on high speed until soft peaks form. Garnish tart with whipped cream and coconut. Chill 2 hours.
TIP *To toast nuts: Place nuts in dry nonstick skillet. Cook over medium heat, shaking pan until nuts are lightly browned. Remove from pan immediately to avoid over-browning.
TIP ** To toast coconut: Spread coconut on microwave-safe plate. Microwave on HIGH 30 seconds. Toss with fork. Repeat as needed. Remove from plate immediately to avoid over-browning.