Special equipment: four 8-inch round cake pans, cake leveling tool (optional), 2 piping bags fitted with 1/2-inch round piping tips (plain pastry tube 806), offset spatula or bench scraper, cake turntable (optional), cake icing smoother (optional), cake stand (optional), 1 lollipop stick
For the confetti cake: Preheat the oven to 350 degrees F. Grease four 8-inch round cake pans with flour-based baking spray and set aside.
In the bowl of an electric mixer, cream the butter and granulated sugar until light and fluffy, 3 minutes. Add the eggs, one at a time, mixing well after each addition. Mix in the vanilla extract.
Sift together the flour, baking powder and salt. Add the flour mixture to the butter mixture alternately with the milk in three additions; begin and end with the flour. Mix on low speed until the batter is smooth and thoroughly combined. Fold in the confetti sprinkles.
Bake the cakes for 25 to 35 minutes, or until the cakes spring back when pressed in their centers. Cool for 10 minutes in the pan. Turn out onto cooling racks. Let cool completely.
Level the cakes using a large serrated knife or cake leveling tool. Transfer the cake scraps to a bowl and cover with plastic wrap. Reserve these for later use.
For the buttercream frosting: Cream the butter and confectioners' sugar together on low speed in the bowl of an electric mixer. When the mixture is combined, increase the speed to high and whip until light in color. Turn the mixer off and add the vanilla extract and 1/3 cup heavy cream. Beat again until the frosting is light and fluffy. Add additional heavy cream if the mixture is too thick to spread or pipe.
Remove two-thirds of the white frosting from the mixing bowl and transfer to a separate bowl; cover with a damp towel to prevent the frosting from drying out. Tint the remaining frosting with the lavender gel food color. Add a little at a time until you reach the desired color intensity. Transfer the lavender frosting to a piping bag fitted with a decorator tip with a 1/2-inch round opening (plain pastry tube 806). Transfer half of the reserved white frosting to a piping bag fitted with a decorator tip with a 1/2-inch round opening (plain pastry tube 806).
Use the remaining white frosting to fill the cake layers and apply a thin crumb coat to the outside of the cake. Use an offset spatula or bench scraper to even the frosting. Place the cake in the refrigerator to chill until the frosting is firm, about 30 minutes. You will have a little frosting left over and this should be reserved for later use.
After the crumb coat layer is well-chilled, use the piping bags with white and lavender frostings to apply alternating colors of frosting around the sides of the cake. Make the lines fat and even. Using a cake turntable is recommended, as it makes this job easier.
Place a bench scraper or cake icing smoother vertically to the side of the frosted cake. Carefully scrape away some of the frosting in a single motion until stripes are revealed. You may need to make several passes before the frosting is completely even. Wipe frosting away from the scraper after each use. Apply frosting to the top of the cake, making it as level as possible. Transfer the cake to the refrigerator to chill while you prepare the pink ganache.
For the pink ganache: Place the chocolate and cream in a microwave-safe bowl. Heat at 100 percent power for 30 seconds and then stir until completely melted and smooth. Add pink food color a little at a time until the desired hue is achieved.
Remove the cake from the refrigerator. At this point the cake should be firm enough to transfer to a cake stand using a spatula; do this now if desired. Use a spoon to drizzle some of the ganache onto the center of the cake, avoiding the edges. Use a spoon to gently push the pooled ganache over the edges of the cake to create a drip effect. Reserve the unused ganache.
For the ice cream cone cake pop and assembly: Crumble the reserved cake scraps using your fingers. Transfer the crumbs to a large bowl and add 2 tablespoons of the reserved buttercream. Mix until thoroughly combined. The mixture should hold together when squeezed in the palm of your hand. If it is too crumbly, add more buttercream 1 tablespoon at a time until the correct consistency is achieved.
Pack two handfuls of the mixture into a ball the size of a scoop of ice cream (you may place the ball against the sugar cone to gauge size). Roll it until the outside is as smooth as possible. Pack more of the mixture into the sugar cone and insert a lollipop stick into the center. Thread the ball onto the lollipop stick and press it onto the top of the sugar cone. Use a spoon to cover the ball with the leftover pink ganache. If the ganache is firm, reheat at 10-second intervals in the microwave until smooth and pourable. Allow the excess ganache to drip back into the bowl.
Turn the ice cream pop upside down and insert it into the cake at a slight angle. Pour more ganache over the ball portion if needed to make it opaque. Cover the ice cream ball portion with sprinkles. Use a mixture of large and small confetti sprinkles to decorate the top edge and bottom edge of the cake.
Tips for success: Avoid using white chocolate chips for the ganache. Chips often contain stabilizers to help them hold their shape during baking. That means they don't melt as smoothly when heated. Use white chocolate baking bars instead, and chop them finely so they will melt evenly. You can find these in the baking aisle next to the chocolate chips. When using the bench scraper to level the cake stripes, it may take several passes to achieve a smooth appearance. If you're having trouble getting an even result, warm your bench scraper or cake smoother in hot water and wipe it dry before using it again. The warm metal will slightly melt the surface of the buttercream and create a smoother finish. The ice cream cake pop ball can be dipped in ganache 2 to 3 times for maximum coverage before placing it on the cake. Be sure to let all of the excess ganache drip back in the bowl before adding a second coat. When turning the ice cream cone upside down to insert into the cake, the ball may want to separate from the cone. You can hold the ball on with a finger while applying it to the cake. Any blemishes can be covered with more ganache once the ice cream cone is anchored onto the cake.