Lemon Ombre Cake

Directions

1. 1
   Preheat oven to 350°F. Grease three 5-inch cake pans, and line bottoms with parchment paper.
2. 2
   In a large bowl, sift the flour, baking powder, baking soda and salt.
3. 3
   In another bowl, whisk sour cream, lemon zest, juice and vanilla.
4. 4
   Beat butter and sugar together on medium speed in a bowl of a standing mixer until light and fluffy. Beat in eggs, one at a time, until blended. Reduce the speed to low and beat in 1/3 of the flour mixture, followed by half of the sour cream mixture. Repeat with another 1/3 of the flour mixture and the remaining sour cream mixture. Beat in the remaining flour mixture until just incorporated.
5. 5
   Evenly distribute the batter into the prepared cake pans and spread evenly. Bake for 18 to 20 minutes or until wooden pick inserted in cake comes out clean. Cool in pan on wire rack for about 10 minutes before inverting on rack. Let cool completely before frosting.
6. 6
   To prepare buttercream, beat butter for a few minutes in a standing mixer with the paddle attachment on medium speed. Add powdered sugar and turn your mixer on low, beat until the sugar incorporates with the butter. Add vanilla, heavy cream, lemon zest and juice, beat on medium speed for another 3 minutes, or until buttercream becomes light and fluffy.
7. 7
   To assemble the cake, place one cake layer on your serving plate and spread with 1/4 cup frosting. Place another cake layer on top, and gently press down a little bit. Spread with another 1/4 cup frosting. Place the last layer of cake on top, smear a light coating of frosting on the top and sides of the cake.
8. 8
   Divide the remaining buttercream into 3 bowls, with one of them a little more than the other two to frost the top of the cake. Tint one of the other two bowls with 4 drops of coloring paste to create bright yellow color. Tint the last one with one drop of coloring paste to create light yellow color.
9. 9
   Starting at the bottom, carefully smear the side with the bright yellow buttercream, followed with light yellow buttercream on the middle part, and the white on the top of the cake. Use a mental spatula to smooth frosting all over the cake, to blend the colors together and create rustic stripes effect.
10. 10
    This step is optional: Use an offset spatula to gently smear horizontal strokes against the sides of the cake.
11. 11
    Cover and refrigerate the cake. Leave out in room temperature for at least 1 hour prior to serving.