In a medium bowl, beat the softened butter and 3/4 cup cane sugar together until light and fluffy, about 2-3 minutes. This creaming process incorporates air into the dough, which helps the cookies rise and become tender. Add the egg and beat until fully incorporated and the mixture is smooth. I find that room temperature ingredients mix much more evenly, so make sure your butter is soft enough to leave an indent when you press it but still holds its shape.

In a separate small bowl, whisk together the flour, cream of tartar, baking soda, and salt. Mixing these dry ingredients separately ensures the leavening agents (baking soda and cream of tartar) are evenly distributed throughout the dough, which gives you consistent rise and that signature snickerdoodle tang. Set this mixture aside until you're ready to combine it with the wet ingredients.

Add the dry ingredient mixture from Step 2 to the creamed butter mixture from Step 1, stirring gently until a cohesive dough forms. Don't overmix—just combine until no streaks of flour remain. Transfer the dough to the refrigerator for 15 minutes. This chilling step is crucial because it firms up the dough, making it easier to roll and shape, and it also allows the flavors to develop slightly. Cold dough spreads less during baking, giving you thicker, chewier cookies.

While the dough chills, preheat your oven to 350°F and prepare your baking sheet by lining it with parchment paper or a silicone baking mat. In a small bowl, mix the 3 tablespoons of ground cinnamon with the 3 tablespoons of cane sugar. I prefer using freshly ground cinnamon from whole quills when I can find them—the aroma and flavor are noticeably more vibrant than pre-ground. Having this coating ready and your oven preheated means you can move quickly once the dough is ready.

Remove the dough from the refrigerator. Scoop approximately 1 tablespoon of dough at a time, roll it gently between your palms into a smooth ball, then immediately roll it in the cinnamon-sugar mixture from Step 4 until evenly coated. Place each coated ball on the prepared baking sheet, spacing them about 2 inches apart—they'll spread slightly as they bake. Working quickly keeps the dough from warming up too much, which maintains that tender texture we're after.

Bake the cookies for 10 minutes at 350°F. They should be set around the edges but still soft in the center—they'll look slightly underbaked, which is exactly right. Remove the baking sheet from the oven and immediately press one unwrapped Hershey's Kiss into the center of each warm cookie, pressing gently until it's anchored but not pushed all the way through to the bottom. The residual heat will soften the chocolate just enough to make it stick without melting completely. Let the cookies cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.