In a large pan, melt the sugar and corn syrup over medium heat until it barely comes to a boil. Remove from heat and stir in the peanut butter. Add cheerios, 2 cups at a time and stir until fully coated.
Press the cheerio mixture evenly into the baking dish.
If adding chocolate, melt the chocolate chips in the microwave for 1 minute until smooth. Then drizzle on top of the bars.
Store in an airtight container for 3-5 days (if they last that long)!
For a healthier alternative, replace sugar and corn syrup with 1 cup honey.