Preheat your oven to 350º Fahrenheit and line a couple cookie pans with parchment paper.
In the bowl of a stand mixer fitted with the paddle attachment, cream together the butter and peanut butter until smooth. Add in the brown sugars and beat until pale and fluffy.
Scrape down the sides of the bowl add the eggs and beat until fluffy. Add in vanilla and beat until combined.
In a small bowl, whisk together four, oats, baking soda, corn starch, cinnamon and salt. Add in two additions to the wet ingredients, beating on low speed until completely combined. The batter may seem a bit soft, but don't worry - this is what you want.
Add in the chocolate chunks, pretzel pieces, roasted peanuts and toffee bits; mix on low until evenly distributed.
Using a cookie scoop or two teaspoons, scoop your batter out into about 1 tablespoon portions out onto your baking sheets leaving at least 1.5 to 2 inches between each cookie. I usually put no more than 12 onto a large tray.
Bake for 10 until the edges are golden brown. Do not overbake the cookies in order to have the softest, chewiest cookies.
Remove from the oven and allow to cool for at least five minutes on the pan, then move to a wire rack to cool completely.
Store in an airtight container.
Notes
The calories shown are based on the recipe making 30 cookies, with 1 serving being 1 cookie. Since different brands of ingredients have different nutritional information, the calories shown are just an estimate. **We are not dietitians and recommend you seek a nutritionist for exact nutritional information.**
If you don't have quick cook oats, put old fashioned oats through the food processor to make the oats small, then use those.
If you like extra thick cookies, refrigerate the dough for at least 30 minutes before baking.