1. Preheat the oven to 350°F and line a 9×13-inch baking pan with parchment paper.

2. Beat the softened butter, brown sugar, and granulated sugar until light and fluffy.

3. Mix in the eggs one at a time, then add the vanilla extract.

4. In a separate bowl, whisk together the flour, baking soda, and salt.

5. Add the dry ingredients to the wet ingredients and mix just until combined.

6. Fold in the chocolate chips, candy-coated chocolates, crushed pretzels, and toffee bits, saving a little for the top.

7. Press the dough evenly into the prepared pan and scatter the reserved mix-ins over the surface.

8. Bake for 24 to 30 minutes, until the edges are golden and the center is just set.

9. Cool the bars completely in the pan.

10. Spread the frosting or whipped topping over the cooled bars.

11. Finish with crushed peppermint candies or sprinkles.

12. Slice into bars and serve.