Place a skillet over medium-low heat. Add the nuts and spread them in a single layer. Cook stirring occasionally for about 3-8 minutes. Once they’re brown and fragrant remove the pecans and set to the side to cool. To bake the nuts instead: Preheat oven to 350 degrees. Line a rimmed baking sheet with parchment paper. Spread the nuts evenly on a baking pan and bake stirring occasionally for 7-10 minutes or until the nuts are fragrant. Set to the side. Toasting step is optional. See notes below before you began toasting the nuts.
Preheat the oven to 350 F Grease 2 8 inch round cake pans and line with parchment paper.
In a large bowl, sift together 2 cups of flour, the cinnamon, cloves, nutmeg, ginger, salt, baking powder, and baking soda. Whisk together.
In another large bowl, beat the granulated sugar, and butter with an electric mixer on medium speed just combined. Add the vegetable oil then the eggs one at a time. Beat until combined. To the batter, add the carrots, pineapple, raisins and toasted pecans. With a rubber spatula, fold into the batter. With the mixer on low setting, gradually add half of the flour to the wet ingredients. With a rubber spatula, mix until combined.
Pour half of the cake batter into one of the prepared pans and the remaining into the other pan. Smooth the tops. Tap the pans on the counter a few times to remove air bubbles trapped in the batter. Doing so will help level out the top of the cakes.
Bake for 25-30 minutes, or until a fork inserted in the center of a cake comes out clean with barely any crumbs. Cool on a wire rack for about until cool to the touch.
Remove the cakes from the pans and wrap them in plastic wrap then place each into a ziploc bag and refrigerate for about an hour. See notes below.
Make the frosting: In a large bowl, beat together the softened cream cheese, butter and vanilla extract with an electric mixer on medium-low speed until smooth and fluffy.
Add the powdered sugar, ½ cup at a time, beating on low speed until combined then beat on medium high speed until the icing is smooth and creamy.
Assemble the cake: Place the cake on a cake stand or serving platter. Top with ⅓ of the frosting. Smooth the frosting to edges. Then top with the last layer. Finish frosting the top and the sides. With your hands slightly cupped, gently press the walnuts into the icing on the sides of the cake. Chill for 60 minutes then slice.