=== CAKE ===
2     cups          all-purpose flour
2     teaspoons     baking soda
1     teaspoon      salt
1     teaspoon      ground cinnamon
2     cups          sugar
1 1/4 cups          canola oil
4     large         eggs
3     cups          grated peeled carrots
1 1/4 cups          coarsely-chopped walnuts
2     tablespoons   minced peeled ginger
                    === ICING ===
10    ounces        cream cheese (such as Philadelphia)
5     tablespoons   unsalted butter
2 1/2 cups          powdered sugar
1/4   cup           pure maple syrup
12                  walnut halves