How about this one?
Courtesy Gourmet Mag
FOR CAKES
2 cups coarsely grated zucchini (10 ounces)
2 1/2 cups all-purpose flour
1 1/4 teaspoons baking soda
1 1/2 teaspoons ground cinnamon
3/4 teaspoon ground ginger
1/2 teaspoon ground nutmeg
1/2 teaspoon salt
3/4 cup well-shaken buttermilk
1 teaspoon pure vanilla extract
1 stick unsalted butter, softened
1 cup packed light brown sugar
1 large egg
1 cup walnuts (4 ounces), chopped
FOR FILLING
1 (8-ounce) package cream cheese, softened
1/2 stick unsalted butter, softened
1 1/2 cups confectioners sugar
1 teaspoon pure vanilla extract
Scant 1/4 teaspoon salt
MAKE CAKES:
Preheat oven to 350F with racks in upper and lower thirds. Butter 2 large baking sheets.
Squeeze handfuls of zucchini wrapped in a kitchen towel to remove moisture.
Whisk together flour, baking soda, spices, and salt until combined. Whisk together buttermilk and vanilla in a small bowl.
Beat together butter and brown sugar in a large bowl with an electric mixer at medium-high speed until pale and fluffy, about 5 minutes. Add egg and beat until combined well.
At low speed, mix in flour and buttermilk mixtures alternately in batches, beginning and ending with flour mixture and mixing until smooth. Mix in zucchini and walnuts until just incorporated.
Spoon 1/4-cup mounds of batter 2 inches apart on baking sheets. Bake, switching position of sheets halfway through, until tops are puffed and golden and spring back when touched, 18 to 22 minutes. Transfer with a spatula to a rack to cool completely.
MAKE FILLING:
Beat together cream cheese, butter, confectioners sugar, vanilla, and salt with cleaned beaters at medium-high speed until smooth, about 3 minutes.
ASSEMBLE PIES:
Spread a rounded 2 Tbsp filling on flat sides of half of cakes and top with remaining cakes.
COOKS NOTE: Whoopie pies keep, chilled in an airtight container, 3 days. Bring to room temperature before serving.