Neapolitan Icing

To prepare vanilla icing, place powdered sugar, meringue powder, and vanilla in bowl of a heavy-duty stand mixer. With mixer running on medium speed, gradually add 7 tablespoons of the water. Beat until well combined, about 3 minutes, stopping to scrape sides as necessary. If necessary, add up to 1 more tablespoon water, and beat until desired consistency is reached. Set aside.

To prepare strawberry icing, place powdered sugar, jam, meringue powder, and vanilla in bowl of a heavy-duty stand mixer. With mixer running on medium speed, gradually add 6 tablespoons of the water. Beat until well combined, about 3 minutes, stopping to scrape sides as necessary. If necessary, add up to 1 more tablespoon water, and beat until desired consistency is reached. Set aside.

To prepare chocolate icing, place powdered sugar, unsweetened cocoa, meringue powder, and vanilla in bowl of a heavy-duty stand mixer. With mixer running on medium speed, gradually add 9 tablespoons of the water. Beat until well combined, about 3 minutes, stopping to scrape sides as necessary. If necessary, add up to 1 more tablespoon water, and beat until desired consistency is reached.  

To assemble, place an offset spatula in hot water for 3 to 5 seconds. Dip right edge of 1 the treat (about 1/3) into first flavor icing, and smooth edges using warm offset spatula; wipe spatula clean. Dip left edge of the treat (about 1/3) into second flavor frosting and smooth edges with offset spatula; wipe spatula clean. Transfer treat to a wire wrack. Repeat procedure with remaining baked goods. Let sit at room temperature until icing is set, about 30 minutes.