Preheat oven to 350°F (180ºC). In large bowl, whisk together flour, baking powder, cinnamon, baking soda, salt, nutmeg and ginger. Set aside. In separate bowl, use hand-mixer to beat eggs with sugar, oil, maple syrup, orange zest and vanilla until blended.
Stir wet ingredients into dry ingredients just until moistened. Fold in carrots and pineapple. Scrape into greased and floured or parchment paper-lined 9 x 13-in. (3-L) baking pan. Smooth top of batter.
Bake 35 to 40 min., or until a cake tester comes out clean when inserted into centre. Cool cake completely in baking pan set on wire rack.
Meanwhile, beat cream cheese with hand mixer until light and fluffy. Beat in butter until blended. Beat in icing sugar and maple syrup just until smooth. Spread icing on cooled cake. Refrigerate at least 1 hr. before serving.
Fold 1/2 cup (125 mL) nuts and/or dried fruit, such as pecans, walnuts, raisins or chopped pitted dates, into batter.