01 - Preheat oven to 350°F. Line a 9x13-inch baking pan with parchment paper, leaving overhang for easy removal.
02 - In a large bowl, beat together softened butter, brown sugar, and granulated sugar until light and fluffy using an electric mixer or sturdy whisk.
03 - Beat in eggs one at a time. Mix in vanilla extract until well combined.
04 - In a separate bowl, whisk together flour, oats, baking soda, baking powder, salt, and cinnamon.
05 - Gradually add the dry ingredient mixture to the wet mixture, mixing until just combined.
06 - Fold in chocolate candies and semisweet chocolate chips.
07 - Evenly spread the dough into the prepared baking pan.
08 - Combine granulated sugar and ground cinnamon for the topping in a small bowl.
09 - Sprinkle the cinnamon sugar topping evenly over the dough.
10 - Bake for 23 to 27 minutes, until edges are golden and a toothpick inserted in the center comes out with moist crumbs.
11 - Allow to cool completely in the pan before lifting out and cutting into bars.