Purple Rose Cake

Directions

1. 1
   Preheat the oven to 325°F. Grease an 8 inch diameter springform pan. For the batter, beat the sugar, vanilla seeds, 9 tbsp butter and 1/2 cup cream cheese with the whisk of a mixer until creamy. Beat in the eggs one at a time. In a separate bowl, mix the flour, baking powder and a pinch of salt together then beat into the butter mixture along with 2 tbsp lemon juice and zest. Spoon into the pan and smooth the top. Bake for 40-45 mins, until a skewer comes out clean, then cool.
2. 2
   Turn the cake out of the pan and slice horizontally into 4 pieces by inserting a knife into the center and rotating the cake around it. Set aside the top slice and spread each of the remaining slices with 1/3 of the jam.
3. 3
   For the buttercream frosting, beat 18 tbsp butter and 2/3 cup powdered sugar until creamy. With a spatula, stir in 1 cup cream cheese. Set aside 3 tbsp of the mixture and spread 1/3 of the remainder over each layer of jam. Stack the slices, pressing the top slice gently on top. Spread the reserved buttercream frosting thinly on the top and sides of the cake and chill for 30 mins.
4. 4
   Meanwhile, for the decorator icing, beat the remaining butter and powdered sugar until creamy. With a spatula, stir in the remaining cream cheese. Color pale purple with the food coloring. Spoon 1/3 into a piping bag fitted with a 1/2 inch star nozzle. Add a little more food coloring to the remaining icing and add to the piping bag. Color the remaining buttercream even darker and spoon into the piping bag. Pipe purple rosettes all over the cake. Chill for 30 more mins.