Carrot Cake Cupcakes

Name: Carrot Cake Cupcakes
Ingredients: 1 cup ( 100 g ) chopped walnuts; 2 cups ( 400 g ) sugar; 3 large eggs; 1 cup ( 240 ml ) vegetable oil; 1/2 cup (120ml) buttermilk; 1 tablespoon orange zest (about 1 large orange); 1 teaspoon vanilla extract; 1 pound ( 450 g ) carrots, grated (about 3 1/2 cups); 3 cups ( 400 g ) all-purpose flour; 2 teaspoons baking powder; 1 teaspoon baking soda; 1 teaspoon kosher salt; 1 teaspoon ground cinnamon; 1/2 teaspoon ground cardamom; 1 cup unsalted butter, softened; 16 ounces Philadelphia cream cheese; 2 cups powdered sugar, sifted