Coconut Pineapple Cake

Serves 8. Coconut Buttercream 2 2/3 cups sweetened flaked coconut Heat oven to 350 F. Butter two 8 inch square (2 inch deep) cake pans. Sift flour with salt into small bowl. Heat eggs and sugar in large metal bowl set over pot of simmering water, gently whisking constantly till lukewarm. Remove bowl from heat and add vanilla. Beat on medium high speed till thick, pale and tripled in volume, 5-10 minutes. Sift flour and salt mixture over eggs in 2 batches, folding gently but thoroughly after each batch. Fold in melted butter till combined. Divide batter evenly between prepared pans, smoothing tops. Bake 15 minutes till toothpick inserted near center comes out clean. Cool in pans on racks 5 minutes. Invert onto racks to cool completely. Stir pineapple, sugar, cornstarch and lemon juice together in saucepan till cornstarch is dissolved. Bring to boil, stirring constantly, then simmer, stirring, for 3 minutes. Cool completely, stirring occasionally. Bring water and sugar to boil, stirring till sugar is dissolved. Remove from heat. Stir in rum. Transfer to small bowl and chill till ready to use. Trim cake edges if necessary and cut each horizontally in half with long serrated knife to form 4 layers. Put 1 layer, cut side up, on serving plate. Brush with some syrup, spread half of filling over syrup. Top with second cake layer and brush with syrup. Spread with 2/3 cup buttercream. Top with third cake layer. Brush with syrup. Spread with remaining filling. Top with fourth layer, cut side down, and brush with remaining syrup. Frost top and sides of cake with remaining buttercream. Coat with coconut.