Preheat oven to 350°F (175°C).

Grease and flour two 9-inch layer pans.

Sift together flour, cocoa, baking powder, cinnamon, salt, and cloves in a bowl.

In a large bowl, cream together butter and sugar until light and fluffy.

Beat in mashed potatoes and egg yolks.

Gradually add the sifted dry ingredients to the wet ingredients, mixing until just combined.

In a separate bowl, beat egg whites until stiff peaks form.

Gently fold the egg whites into the batter.

Stir in pecans, raisins, and cherries.

Pour batter into the prepared pans.

Bake for 40 minutes, or until a wooden skewer inserted into the center comes out clean.

Let cool in pans for 10 minutes before inverting onto a wire rack to cool completely.

Prepare the caramel frosting:

Melt butter in a saucepan over medium heat.

Stir in brown sugar until smooth.

Bring to a boil over low heat, stirring constantly, and boil for 1 minute.

Remove from heat and stir in milk.

Return to low heat and bring just to a boil.

Remove from heat and cool to 100°F (38°C).

Gradually beat in confectioners' sugar until smooth.

Beat at high speed until frosting holds its shape (about 30-60 seconds).

Stir in vanilla extract.

To assemble the cake:

Place one cake layer on a serving plate and spread with half of the frosting, letting it drip down the sides.

Top with the second cake layer and spread with the remaining frosting, allowing it to drip down the sides.

Swirl the top of the cake with the back of a spoon.

Arrange pecan halves on top of the cake.