Heat oven to 350° Fahrenheit. Grease bottoms only of 2 round, 8 1/2 or 9 1/2 in pans, with shortening. Lightly flour.

Beat cake mix, water, oil, and eggs in large bowl with electric mixer on low speed 30 seconds. Beat on medium speed 2 minutes, scraping bowl occasionally. Pour into pans.

Bake 29-39 min or until a toothpick inserted in center, comes out clean. Cool 10 minutes. Run knife around sides of pans to loosen cakes; remove to wire rack. Cool completely, about 1 hour.

Meanwhile, stir sugar, rum, and coffee ( dry) in 1 qt saucepan, until coffee is dissolved. Heat to boiling, stirring occasionally, remove from heat. Cool completely. Make Mascarpone filling and chocolate ganache.

Cut each cake layer horizontally to make 2 layers each. Brush about 1 tablespoon of rum mixture over cut side of each layer; let stand 1 minute to soak into cake. Fill each layer with about 2/3 cup mascarpone filling. Frost side and top of cake with chocolate ganache. Store I'm Refrigerator.

*Mascarpone Filling *

Beat all ingredients in medium bowl with electric mixer on low just until blended

* Chocolate Ganache*

Heat all ingredients in 1 qt saucepan over low heat, stirring frequently, until chips are melted and mixture is smooth. Refrigerate about 30 minutes, stirring occasionally, until slightly thickened

*from Betty Crocker SuperMoist Cake Mix Recipes* April 2004 edition