Directions Heat oven to 325°F. Coat two 8 x 2-in. heart-shaped cake pans* with nonstick spray. Line bottoms with wax paper. Cake: Put cocoa powder and boiling water in a medium bowl; stir until smooth. When cool, add next 4 ingredients. Beat with mixer on medium speed until blended. On low speed, add flour, baking soda and salt. Beat just until smooth (batter is thin). Divide between pans. Bake 45 to 55 minutes until a wooden pick inserted in center of cakes comes out clean. Cool in pans on a wire rack 10 minutes. Run knife around edges of cakes, invert on rack, peel off paper and cool completely. Frosting: Beat butter and vanilla in a large bowl with mixer on medium speed until creamy. Reduce speed to low and beat in 1⁄2 cup sugar, then melted chocolate. Alternate beating in remaining sugar and 1⁄2 cup cream. Increase speed to medium; beat, adding more cream if needed, until spreadable. To assemble: Turn cakes right side up. With a serrated knife, trim tops level if necessary. Place 1 layer top side down on serving plate. Spread top with 1 cup frosting. Add other layer, top side down. Brush any crumbs off cake. Coat with a thin layer frosting, then spread and swirl on remaining frosting. Shortly before serving: Place hearts on cake. Line a baking sheet with wax paper. Have ready assorted-size heart-shaped metal cookie cutters and red paste food color. Melt 1⁄2 cup semisweet chocolate chips as package directs. Pour onto lined baking sheet and spread with a metal spatula to a 6 1⁄2-in. square. Refrigerate 5 minutes until set. Fill a shallow bowl with hot water. Dip cookie cutter(s) in water about 30 seconds, tap off excess water and cut out chocolate hearts. Refrigerate until needed. Repeat with 1⁄2 cup milk chocolate chips. Melt 1⁄2 cup white chocolate chips as bag directs. Remove about 1⁄4 and tint red. Spread white and red chocolate on lined baking sheet; proceed as above. Cake: can be baked and frosting made up to 2 days ahead. Wrap layers separately; store at cool room temperature. Refrigerate frosting. To use, bring frosting to room temperature; beat until spreadable. The hearts can be made up to 1 week ahead. Refrigerate.