MAKE WHIPPED WHITE CHOCOLATE FROSTING. Do this first as it needs time to chill
Have chopped white chocolate in a large bowl. Heat cream until hot but not boiling, pour over white chocolate. Let stand 1 minute then stir until smooth stirring in vanilla and salt. Refrigerate until completely cold, at least 4 hours or overnight. Don't whip until cupcakes are cool and ready to frost
MAKE CUPCAKES
Preheat oven to 325F. Line 12 standard cupcake tins with paper liners
Wkisk flour, baking powder and salt in a bowl, set aside
Whisk in another bowl milk and anilla and set aside
In another large bowl beat sugar and butter until light and fluffy
Beat in sour cream until smooth
Stir in flour alternating with milk in 3 additions
With clean beaters beat egg whites with cream of tarter until it holds stiff peaks . Fold into batter in 3 additions until blended
Divide batter evenly into prepared cupcake tins
Bake 17 to 20 minutes until a toothpick comes out just clean
Have 12 truffles unwrapped
Cut a slit in the top of each cupcake as soon as they come out of the oven. Press a truffle in each slit and gently press even with the top. Truffle will melt to cupcake. Remove from tins carefully and cool completely before frosting
FINISH WHIPPED WHITE CHOCOLATE MASCARPONE FROStING
Beat chilled cream and white chocolate until it it has soft peaks
Beat mascarpone, confectioner's 6 and 1/2 teaspoon vanilla until smooth
Stir iinto white chocolate mixture and beat until light and fluffy
Frost cupcakes with frosting, Store cupcakes, covered in refrigerator but serve at room temperature.Top each cupcake with some red and purple sprinkles a fresh raspberry before serving
