Prepare Filling: Bring first 3 ingredients and 3 cups cranberries to a boil in a medium saucepan over medium-high heat. Boil, stirring often, 5 to 6 minutes or until cranberries begin to pop. Transfer 1 cup cranberry mixture to a small bowl, and stir in remaining 1/2 cup whole cranberries. (This will be the Cranberry Topping.) Transfer remaining hot Cranberry Filling mixture to another small bowl. Cool both mixtures completely (1 hour). Cover; chill 8 hours.
Prepare Buttercream: Beat butter and next 2 ingredients at medium speed with an electric mixer 1 to 2 minutes or until creamy. Gradually add powdered sugar alternately with orange juice. Beat at low speed until blended and smooth after each addition. Stir in vanilla. If desired, add 1 to 2 Tbsp. milk, 1 tsp. at a time, beating until frosting reaches desired consistency.
Place 1 Basic White Cake layer on a serving platter. Spoon 1 1/2 cups buttercream into a zip-top plastic freezer bag. Snip 1 corner of bag to make a small hole. Pipe a ring of frosting around cake layer just inside the top edge. Spread cake layer with half of chilled Cranberry Filling (without whole berries), spreading to edge of piped frosting. Top with second cake layer. Repeat procedure with frosting and remaining Cranberry Filling (without whole berries). Top with third layer. Spread remaining buttercream over top and sides of cake. Pipe a ring of frosting around top cake layer just inside the top edge. Spread Cranberry Topping (with whole berries) over top cake layer, spreading to edge of piped frosting.