Place the first layer of sponge on a 8 inch thin cake board, flat size down. Brush the cake with champagne syrup using a pastry brush (repeat this process with remaining layers of cake). Fit a 1/2 inch round nozzle into a piping bag.
Pipe a dam of buttercream around the cake for clean even layers of frosting. Fill the dam with frosting and use an off set spatula to spread the frosting carefully. You can also pipe the entire layer of frosting, if you don’t want to use the offset spatula to spread the frosting. Spoon 3 tablespoons of strawberry conserve over buttercream, smoothing it over buttercream.
Repeat with remaining 3 layers of vanilla cake, until all three layers of cake are stacked.
Wrap cake with plastic cling film and chill for 1-3 hours.
Remove cake from fridge. Spread a thin layer of white chocolate buttercream on the sides and then top of cake. It helps to use a turntable when frosting a cake. Hold a scraper flat against the side of the cake and then turn the turntable and scraper to make a nice, smooth coat of icing. Smooth the top of cake with scraper, drawing the peaks o the top edges of cake into the centre.
Chill crumb coated cake in fridge for 30 minutes until buttercream is nice and firm.
Once cake is chilled, cover evenly with white chocolate buttercream using an off set spatula and then use a scraper to smooth the edges.
Chill cake for 1 hour.
Place a large baking tray on a turntable and place cake on the baking tray.
Grab a handful of confetti, starting at the bottom and press them into the side of the cake. Spin the turntable as you work. Reuse the confetti that have fallen at the base of the cake.
Transfer some of the buttercream into a piping bag fitted with a large french open star tip. Pipe swirls around the top edge of the cake.
Pipe buttercream swirls on cupcakes as well.