Step 1

Begin by making the butterscotch brittle. In a small saucepan, add the sugar, water, butter and salt.

Step 2

Put the pan on medium heat and let the butter melt, undisturbed, until it is almost fully melted. Give everything a swirl with a spatula, and then let it cook, undisturbed, until the mixture starts bubbling slightly.

Step 3

Use your spatula to stir occasionally, and wait for the mixture to turn noticeably darker in color. It will go from glassy clear to slightly golden. Remove it from the heat.

Step 4

Immediately add the 1/8 tsp of baking soda and stir until it is dispersed. It'll start bubbling slightly and will lighten even more in color. Pour this directly onto a parchment lined baking sheet. Smooth with the spatula and let this cool either at room temperature or in the fridge.

Step 5

While the butterscotch is cooling, wipe out the pan you used.

Step 6

Preheat the oven to 400F.

Step 7

In the same pan, brown the 16 tbsp of butter. Do this by putting the pan on medium-low heat and letting the butter fully melt. Stir occasionally, until you see the milk solids start to separate and form flecks on the bottom of the pan. Let the butter fizz a bit and continue to stir. Continue this for about 2-3 minutes, or until the milk solids start to become a golden brown. Turn the heat to medium and stir consistently for 1 more minute, then remove the butter from the heat and stir until it is a deep, dark gold brown.

Step 8

Add the chopped up rosemary to a bowl, pour the brown butter into the bowl and whisk to bring the temperature down. Add in the butternut squash purée here and whisk (do not do this if you are using an egg instead). Move the brown butter to the fridge to cool for 5 minutes.

Step 9

In the bowl of a stand mixer, add the brown sugar, white sugar and vanilla. Pour in the brown butter when it has cooled slightly. Add the egg during this step if you are using it instead of the butternut squash purée. Use the paddle attachment of the mixer to mix on medium. Mix for about 3-4 minutes or until the mix is light and fluffy.

Step 10

While the mixer is running, whisk together the flour, cornstarch, pumpkin pie spice, baking powder and salt in a bowl.

Step 11

Stop the mixer and add the dry ingredients a little at a time to the dough, using a spatula to mix it in until smooth. When the dry ingredients are fully incorporated, the dough should be fluffy.

Step 12

Line a large baking sheet with parchment paper. Use a scale to measure out nine even 4 ounce scoops of dough. These will be huge, bakery-style cookies, so place them evenly on the baking sheet, leaving plenty of room for them to spread.

Step 13

Break your hardened butterscotch into "pieces" and place a large piece in the center of every cookie.

Step 14

Bake at 400°F for 10-11 minutes - a trick here is to take them out when they still look and feel underdone, just trust me!

Step 15

Smack the baking sheet on the counter a few times to help flatten the cookies. This is an imperative step! They'll come out a bit tall, but smack the sheet on the counter a few times and watch them spread like magic. Use a bowl or cup to swirl around the edges of the cookie, helping to form them into perfect circles.

Step 16

Let the cookies cool for ten minutes to set, and then eat right away if you want a chewy butterscotch. If you want a thin, crisp butterscotch bite, let them cool completely and taste cookie heaven. (I like to store these in the fridge, they taste divine chilled!)