This Frosted Snickerdoodle Bars recipe is everything you love about snickerdoodles in a bar form and frosted with a light and fluffy cinnamon vanilla buttercream.
Preheat the oven to 350 degrees Fahrenheit (175 degrees Celsius). Line an 8x8" or 9x9" baking pan with aluminum foil and set aside.
In the bowl of a stand mixer, cream the butter, sugar, and vanilla until light and fluffy, about 2–3 minutes. With the mixing speed on low, add the egg and egg yolk.
In a separate bowl, whisk together the flour, salt, baking powder, baking soda, cornstarch, cream of tartar, and cinnamon. With mixing speed on low, gradually add the dry ingredients to the wet ingredients, mixing until no flour pockets remain. Be careful not to overmix.
Using a rubber spatula or the palm of your hand, press the dough into the prepared pan. Bake for approximately 22–26 minutes or until very lightly browned on top (be careful not to overbake). Remove from the oven and allow the bars to cool in the pan for 30–45 minutes before frosting.
While the bars are cooling, prepare the frosting by placing the butter in the bowl of a stand mixer. Beat until light and creamy, about 2–3 minutes. With mixing speed on low, add the powdered sugar, cream, vanilla extract, cinnamon, and salt. Beat on high for 2–3 minutes until it becomes fluffy.
Using the foil as handles, remove the cooled bars from the pan. Frost the bars with a thick layer of frosting and garnish with additional cinnamon and coarse sugar.
Notes
Recipe adapted from Sally’s Baking Addiction, Frosted Sugar Cookie Bars.-I used my Trader Joe’s grinder to sprinkle cinnamon and sugar on top. You can use ground cinnamon, coarse or granulated sugar, or skip the topping altogether.-The bars have a thick layer of frosting on top. If you prefer less, simply halve the frosting recipe.To STORE leftover Iced Snickerdoodle Bars, place them in an airtight container at room temperature for up to 3 days. If you want to extend their freshness, transfer them to the refrigerator for up to 5–6 days—just let them come to room temperature before serving so the frosting softens.For FREEZING, wrap individual bars in plastic wrap, then place them in a freezer-safe container. They’ll stay good for about 2 months. To enjoy again, thaw at room temperature or microwave each bar in 5–10 second bursts until soft.