3/4 cup (1½ sticks) unsalted butter, room temperature
2 teaspoon grated lemon rind
Chopped walnuts, for garnish
To prepare cake, preheat oven to 350F. Line bottom of three 8-inch round cake pans with parchment paper. Leave sides of pan dry—no cooking spray needed.
Combine eggs and oil in a large mixing bowl. Beat 2 minutes with a mixer on medium speed. Add 1 cup sugar and continue mixing 2 minutes. Add remaining sugar and mix 3 to 4 minutes.
Combine flour and next 6 ingredients (flour through nutmeg); add to egg mixture, beating on low speed until blended, about 1 minute. Add carrots, walnuts and pineapple; mix until well combined.
Divide batter evenly among pans.
Bake 60 minutes, or until a wooden pick inserted in the center comes out clean.
Cool to room temperature on a wire rack. Run knife around edge of cakes and remove from pans. Wrap in plastic wrap and refrigerate overnight.
To prepare icing, place cream cheese in mixing bowl; beat with a mixer on medium speed until smooth. Add melted chocolate a little at a time, continuing to beat at medium speed. Add butter a little at a time. Scrape down sides of bowl; add lemon rind and beat until combined.
Remove cakes from refrigerator. Ice top of one layer. Place second layer on top; ice top. Place third layer on top; ice top and sides of cake. Press chopped walnuts into sides of cake. Serves 16.