Beat 2 sticks butter, 3/4 cup dark brown sugar and 3/4 cup granulated sugar until fluffy; beat in 1 teaspoon vanilla and 2 eggs. Whisk 2 1/2 cups flour, 3/4 teaspoon baking soda and 1 teaspoon salt, then stir into the butter mixture. Add 1 cup chocolate-covered peanuts, 1/2 cup chocolate-covered raisins and 1/2 cup M&M's. Press scoops of dough into standard-size muffin cups. Bake 20 to 25 minutes at 350 degrees.