Adjust oven rack to lower-middle position; heat oven to 350℉. Lightly grease a 13x9-inch baking pan.
In a large mixing bowl, whisk together melted butter, sugar, eggs and vanilla extract.
In a medium mixing bowl, whisk together flour, cinnamon, baking soda, salt, nutmeg, and cloves.
Gradually add the dry mixture to the wet mixture, stirring well until incorporated. The batter will be very thick, almost cookie dough-like. Stir in ¾ cup toasted chopped pecans and sliced apples.
Spread the batter in the baking pan, and bake at 350℉ for 45 minutes, until a toothpick inserted in the center comes out clean.
Allow the cake to cool for at least 45 minutes. Dust with confectioners sugar before serving. For a more decadent cake, top with caramel buttercream frosting and reserved toasted chopped pecans.