Place the butter, sugars, and vanilla extract in the bowl of a mixer fitted with a paddle or dough beaters. Mix on medium speed until the mixture is completely smooth, approximately 3-4 minutes.
Add the eggs to the bowl and beat on low for 30 seconds, just until combined. The batter may break up a bit, but don’t worry. It will come together when the dry ingredients are worked into the mix. Scrape down the bowl and beaters if necessary to gather the batter together before continuing.
In a small bowl, combine the flour, cornstarch, salt, baking powder, baking soda, and ground cinnamon. Use a dry whisk to mix the dry ingredients and break up any small lumps. You can sift the dry ingredients if you prefer.
Add the dry ingredients in one addition to the mixer bowl. Mix on low speed until the dry ingredients have completely integrated into the dough. This should only take 30-60 seconds depending on the strength of your mixer. Take great care not to overmix the dough as it will encourage the dough to strengthen the gluten in the flour and become tough.
Add the oats, butterscotch chips, and white chocolate chips to the dough and mix on low speed just until combined and well distributed.
At this point, the batter can be baked, chilled in the refrigerator for baking in a few hours, or portioned and frozen for baking at a later date. I often make a batch of dough and keep it in the refrigerator, baking a single evening’s cookies each night. Portioned balls of dough can also be frozen on a small tray and then transferred to a freezer bag for long term storage. Frozen dough can be baked straight from the freezer by simply adding about two minutes to the baking time.
When you are ready to bake cookies, preheat the oven to 325 degrees Fahrenheit and position the oven racks to the top and bottom third of your oven. Line two baking sheets with parchment or a Silpat style reusable baking liner.
Create balls of dough by using two Tablespoons of the chilled dough and rolling into a ball. Flatten the ball slightly to help encourage even baking and place six balls on each baking sheet, spacing evenly to prevent the cookies from merging as they bake.
Bake for 10 minutes, rotating the baking sheets halfway through the baking time to help to ensure that the cookies are evenly baked. The cookies should bake up to an even thickness and dry ever so slightly on top. They may appear to be under baked, but they will firm up upon cooling to room temperature.
Remove the cookies from the oven, allowing them to cool for 5-10 minutes to set up. As with any cookie, these are even more delicious when eaten while still warm with a cup of coffee or cold glass of milk.
Notes
Baked cookies can be stored in an airtight container at room temperature for several days. Dough can be refrigerated for one week and frozen for several months. Our family lives and bakes around nut allergies, so our farmhouse kitchen is nut free. This recipe is delicious when made with one of our nut free favorites: Vermont Nut Free Chocolates butterscotch chips. You can learn all about them at www.vermontnutfree.com.