Combine all ingredients in a double boiler and heat while stirring constantly with a whisk. It’s done when it’s thick enough to coat the back of a smooth.

Refrigerate lemon curd until cool and thick.

Preheat oven to 350℉ and line three 8-inch cake pans with parchment paper and grease the sides.

Beat butter and sugar until light and fluffy, 3-4 minutes.

Add vanilla extract, sour cream and lemon zest and mix until combined.

Add egg whites in two batches, scraping down the sides of the bowl as needed to make sure all is incorporated and smooth.

In a separate bowl, combine dry ingredients. In another small bowl or measuring cup, combine milk and water.

Add half of the dry ingredients to the batter and mix until combined. Add milk/water combination and mix until combined, scraping down the sides of the bowl as needed. Add remaining dry ingredients and mix until smooth.

Divide batter evenly between the three 8-inch pans and bake for 23-25 minutes, or until a toothpick inserted comes out with a few crumbs.

Puree fresh raspberries, then press through a fine mess sieve to remove pulp and seeds. You should end up with about ½ a cup of raspberry liquid.

Combine butter and shortening and beat until smooth.

Add 4 cups of powdered sugar and beat until smooth.

Add raspberry liquid and beat until well combined.

Slowly add remaining powdered sugar, beating until smooth.

Add 1 to 2 tablespoons of milk or water, as needed, to thin out the frosting.

Remove the tops of the cakes with a large serrated knife, so they are flat. Place first cake on serving plate or on a cardboard cake circle.

Top cake with about ¾ cup of raspberry frosting and spread into an even layer. Pipe a dam of raspberry frosting around the outside edge of the cake, then fill it with half of the lemon curd.

Top lemon curd with second layer of cake and repeat another layer of raspberry frosting and lemon curd.

Add final layer of cake, the frost the outside of the cake with the raspberry frosting.

Before the frosting on top of the cake has a chance to firm up too much, use your offset spatula to create the lines on top. Starting from the center, hold the tip of your spatula on the cake at about a 30-45 degree angle. Your cake should be on a turntable so that it’s easy to turn the cake and complete the circle. Make one circle at a time, moving from the center of the cake to the outside.

Pipe several tall swirls of frosting on the back half of the top of the cake, leaving some space between for adding lemon slices and raspberries. Add lemon slices and raspberries to cake.

To make the fondant flowers, use a small blossom cutter. Use a brush to dust a little bit of yellow pearl dust in the center, then add a little bit of sugar water in the center of the flower and press a small pearl sprinkle into the center. Add flowers to cakes.

Cake should be refrigerated until ready to serve. Best served after allowing to sit out for about 30 minutes.