Grate or puree the carrots, toast the walnuts for 10 minutes, then chop them. Once cooled, puree 2/3 cup of walnuts. Mix the vegetable oil, granulated sugar, and brown sugar until smooth. Gradually add the eggs in three parts, mixing until combined. Then add the grated carrots and pureed walnuts.

Sift in the flour, baking powder, cinnamon, and salt. Fold the mixture with a spatula until well combined. Grease a baking pan, line it with parchment paper, and preheat the oven to 350°F. Bake for 30 to 40 minutes.

Once the cake has cooled, cut it in half. Soften the butter at room temperature and beat it with a mixer until creamy. Gradually add the cream cheese in three parts, beating until smooth, then add the powdered sugar and beat until fluffy.

Spread frosting on the first layer of the cake, place the second layer on top, and spread more frosting. Sprinkle chopped walnuts on top and chill in the freezer for 3 hours.