Mississippi Mud Pie Dip and Mississippi Mud Cake

Name: Mississippi Mud Pie Dip and Mississippi Mud Cake
Cuisine: American
Ingredients: 1 container cool whip (dip); 1 package chocolate pudding mix (dip); 1/2 package Oreo cookies (dip); 1/3 c. chopped pecans (dip); 1 c. chopped pecans (cake); 1 c. butter (cake); 1 bar semisweet chocolate baking bar (cake); 2 c. sugar (cake); 1½ c. all-purpose flour (cake); ½ c. unsweetened cocoa (cake); 4 large eggs (cake); 1 tsp. vanilla extract (cake); ¾ tsp. salt (cake); 1 bag miniature marshmallows (cake); ½ c. butter (frosting); ⅓ c. milk (frosting); ¼ c. unsweetened cocoa (frosting); 1 package powdered sugar (frosting); 1 tsp. vanilla extract (frosting)