1-Step 1: Prepare Your Equipment and Oven Begin by preheating your oven to 350 degrees Fahrenheit. This temperature allows the bars to bake evenly without browning too quickly. While the oven heats, prepare your baking pan. Line a 9×9 inch baking pan with parchment paper, leaving some overhang on the sides. This overhang makes it easy to lift the entire cookie bar out after cooling for clean, neat cutting. The parchment paper also prevents sticking, which is essential since this dough contains butter and can adhere to the pan. If you do not have parchment paper, you can grease the pan thoroughly with butter or cooking spray, but parchment gives the cleanest release.

2-Step 2: Cream the Butter and Sugar In a large mixing bowl, beat together the softened butter and sugar until the mixture becomes fluffy and pale. This step is crucial because creaming incorporates tiny air bubbles into the mixture, which helps create a tender, cake-like texture in the finished bars. Use an electric mixer on medium speed for about 2-3 minutes. Stop occasionally to scrape down the sides of the bowl with a rubber spatula to ensure everything blends evenly. The butter should be softened to room temperature but not melted. Melted butter will not cream properly and will result in a dense, greasy cookie bar. If you are looking for other quick treats like easy no-bake recipes, check out our collection of simple snacks. Make sure your butter is softened, not melted, before mixing it really helps the dough come together perfectly without getting too sticky or crumbly.

3-Step 3: Add Egg and Vanilla Once the butter and sugar are properly creamed, add the large egg and vanilla extract. Continue beating the mixture until the egg is fully incorporated and the mixture looks smooth and glossy. The egg provides structure and richness, while the vanilla adds that classic sugar cookie flavor everyone recognizes and loves. This step should take about 1 minute of mixing. The mixture should look uniform with no visible streaks of egg. If your egg was cold from the refrigerator, the mixture might look slightly curdled. This is not a problem and will resolve once the flour is added.

4-Step 4: Incorporate Dry Ingredients Gradually mix in the all-purpose flour and baking powder. Add these ingredients slowly while the mixer runs on low speed to prevent flour from flying out of the bowl. Continue mixing until a thick dough forms. The dough should come together in a ball and pull away from the sides of the bowl. Be careful not to overmix at this stage. Once the flour is incorporated, stop mixing. Overmixing develops gluten in the flour, which can make the cookie bars tough instead of tender. The dough should feel soft and pliable, not sticky or crumbly.

5-Step 5: Fold in the Festive Sprinkles Stir in the sprinkles gently using a rubber spatula or wooden spoon. Folding rather than mixing helps keep the sprinkles intact and evenly distributed throughout the dough. Some sprinkles may bleed their color slightly, which creates a fun, speckled appearance in the baked bars. Use Christmas-themed sprinkles in red, green, and white for the most festive presentation. The more sprinkles you add, the more colorful and celebratory your bars will look. Just be careful not to add too many, as this can affect the structural integrity of the dough.

6-Step 6: Spread and Bake Transfer the thick dough to your prepared 9×9 inch baking pan. Spread the batter evenly using a spatula or the back of a spoon, pressing it down as it is quite thick. Take your time with this step to ensure an even layer that will bake uniformly. The dough will not spread much during baking, so make sure it reaches all corners of the pan. Bake for 20 minutes or until the edges are golden brown and a toothpick inserted into the center comes out clean. The top should look set and may have slight cracks, which is normal for bar cookies. Every oven is different, so start checking at 18 minutes to avoid overbaking.

7-Step 7: Cool Completely Remove the pan from the oven and place it on a wire rack to cool completely. This is one of the most important steps in the entire recipe. The cookie bar needs to be entirely cool before frosting, or the frosting will melt and slide right off. Allow at least 30-45 minutes for cooling. If you are in a hurry, you can place the pan in the refrigerator after the first 15 minutes of room temperature cooling. Once completely cooled, lift the cookie bar out by the parchment paper edges carefully and transfer to a cutting board or serving platter.

8-Step 8: Prepare the Cream Cheese Frosting While the cookie bar cools, make the frosting. Use an electric mixer to blend the powdered sugar, softened butter, softened cream cheese, vanilla extract, and milk. Start on low speed to avoid a cloud of powdered sugar, then increase to medium speed and beat until smooth and creamy. The frosting should be spreadable but not runny. If it seems too thick, add more milk one teaspoon at a time. If it seems too thin, add more powdered sugar one tablespoon at a time. The cream cheese should be fully softened to prevent lumps in your frosting. This cream cheese frosting is what sets these bars apart from ordinary sugar cookies, adding richness and a slight tang that balances the sweetness.

9-Step 9: Frost and Decorate Spread the frosting generously over the cooled cookie bar using an offset spatula or butter knife. Work from the center outward, spreading the frosting to the edges in an even layer. The frosting should be thick enough to hold its shape but smooth enough to spread easily. Immediately sprinkle additional festive sprinkles on top while the frosting is still wet so they stick. Be generous with the decorations for a truly festive appearance. For more easy breakfast and treat ideas, try these mini muffin pancake bites that are perfect for busy mornings.

10-Step 10: Cut and Serve Using a sharp knife, cut the frosted cookie bar into squares. You can make them as large or small as you prefer. A 9×9 inch pan typically yields about 16 standard-sized bars or 24 smaller squares for bite-sized treats. Wipe the knife clean between cuts for neat edges. Serve immediately for a soft, creamy texture, or let the frosting set for a firmer texture. These bars pair wonderfully with milk, coffee, or hot cocoa for a cozy holiday treat. Sugar cookie bars are versatile enough for any occasion and travel well for potlucks and cookie exchanges.