To the bowl of a stand mixer fitted with the paddle attachment (or large mixing bowl with hand mixer), combine the egg, butter, sugars, vanilla, and beat on medium-high speed until light and fluffy, about 5 minutes.

Stop, scrape down the sides of the bowl, and add the cinnamon, allspice, nutmeg, cloves, optional salt, and beat momentarily to incorporate.

Add the flour, oats, baking soda, and beat until just combined, less than 1 minute.

Add the carrots and beat to incorporate, about 30 seconds.

Add the optional butterscotch chips, raisins, and beat to incorporate, about 30 seconds.

Using a medium cookie scoop (about 2 tablespoons) or your hands, scoop out mounds of dough (I made 22) and place them on a large plate. Flatten mounds just slightly with heel of your hand.

Cover plate with plasticwrap and refrigerate dough for at least 3 hours, up to 5 days, before baking. Dough is far too soft and moist, and is unsuitable for baking until it’s been chilled or cookies will spread dramatically.

Preheat oven to 350F, line 2 baking sheets with Silpat Non-Stick Baking Mats, parchment, or spray with cooking spray; set aside. Space dough 2 inches apart (8 per tray) and bake for 9 to 11 minutes (I recommend the lower end of that range), or until tops have just set, even if slightly underbaked and glossy in the center. Cookies firm up as they cool, and baking too long results in cookies that set up too crisp and hard with overdone undersides (The cookies shown in the photos were baked for just over 9 minutes, with trays rotated at the 5-minute mark, and have chewy edges with pillowy, soft centers).

Allow cookies to cool on the baking sheet for about 10 minutes before removing and transferring to a rack to finish cooling.