Heat oven to 180°C. Grease bottoms and sides of three (23cm) round cake pans; lightly flour.
Make cake as directed on box and pour evenly into pans.
Bake 25 to 30 minutes or until toothpick inserted in center comes out clean. Cool 10 minutes; remove from pans to cooling racks. Cool completely, about 1 hour.
In medium bowl, beat vanilla frosting with 5 drops of pink food coloring; set aside.
Cut each cake horizontally to make 2 layers. (Mark side of cake with toothpicks and cut with long, thin serrated knife.) Place 1 layer, cut side up, on serving plate; spread with 75 grams raspberry jam to within 1/2cm of edge. Top with another layer, cut side down; spread with 75 grams frosting. Repeat with remaining layers.
Frost side and top of cake with remaining frosting. Pipe frosting on top of cake. Garnish with fresh raspberries. Store loosely covered.