Royal Icing: In bowl of stand mixer using a whisk attachment, whisk 2 eggs whites until frothy. Gradually add 5 cups powdered sugar on low speed, scraping down sides of bowl periodically. Once sugar has been combined, increase speed of mixer to high and whisk 7 to 10 minutes or until stiff peaks form. Fill a piping bag, fitted with a tip and use immediately.
Peanut Butter Frosting: In large bowl, combine 1 cup SKIPPY® Creamy Peanut Butter and 1 cup powdered sugar. Beat until smooth. Transfer mixture to a piping bag, fitted with a tip.
Assembly: Decorate gingerbread house cut outs with Royal Icing. Pipe Peanut Butter Frosting along edges of gingerbread house, covering all seams and edges. Assemble house. Decorate house with remaining ingredients. Let dry 4 hours or up to overnight.