Easter Egg Cake

Name: Easter Egg Cake
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Cuisine: American
Ingredients: 1 2/3 cup all-purpose flour (213g); 1 cup sugar (228g); 1/4 tsp baking soda (2g); 1 1/2 tsp baking powder (6g); 1/4 tsp salt; 3/4 cup unsalted butter (176g, room temperature); 3 egg whites; 1 tbsp vanilla extract; 1/2 cup sour cream (133g); 1/2 cup whole milk (113g); 2 lbs confectioners sugar (907g); 1 lb butter (456g, unsalted, room temperature); 3 tsp vanilla; 1 tbsp milk; 1/4 tsp kosher salt; Blue food coloring; ½ cup coconut (40g, toasted, sweetened); 2 tsp cocoa powder (nice quality); 4 tsp vanilla extract; 6 chocolate eggs (mini)