Prepare and bake cake according to package directions, using two greased 9-in. round baking pans. Cool for 10 minutes before removing from pans to wire racks to cool completely.
Spread frosting between layers and over top and sides of cake. In a large bowl, combine 1-1/2 cups peanuts, the chocolate kisses and 1 cup marshmallows; set aside.
Arrange remaining marshmallows to form the border of a road across the top of cake. Coarsely chop remaining peanuts and sprinkle inside marshmallow border. Lightly press chocolate mixture over sides and remaining top of cake.
How-To: After the cake is frosted, use 1/2 cup miniature marshmallows to outline a 2-inch wide "road" on top. See road» Lightly press the chocolate kisses, peanuts and miniature marshmallows to evenly distribute the topping on the frosting. See topping»