Frosted Sugar Cookie Bars

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Frosted Sugar Cookie Bars: A Complete Guide

Few treats capture the cozy comfort of home like frosted sugar cookie bars. With their tender crumb, velvety frosting, and touch of sprinkles, these bars transform classic sugar cookies into a treat that thrives at parties, potlucks, or quiet afternoons. Instead of rolling and cutting dozens of cookies, you’ll press the dough into a pan, bake, and frost—all in a fraction of the time. This recipe offers everything you need, from the fundamentals to finishing touches.

Why Frosted Sugar Cookie Bars Stand Out

Frosted sugar cookie bars hit a sweet spot for bakers and eaters alike. They simplify the classic sugar cookie into a more manageable format—no need for cookie cutters, rolling pins, or several baking trays. With just one batch, you can create a sliceable, shareable dessert with crisp edges and a soft, chewy center.

• Effortless and Efficient: The dough comes together quickly and bakes all at once. You spend less time in the kitchen but still get excellent texture and flavor.
• Kid-Friendly: The process—pressing the dough and spreading frosting—is straightforward and perfect for little helpers.
• Customizable: These bars adapt to any season or occasion with a quick change of frosting color or sprinkle style.
• Perfect for Gatherings: They’re easy to cut, transport, and serve, making them a crowd-pleaser at birthdays, showers, or bake sales.

Ingredients: Building Blocks of Flavor and Texture

Every ingredient in frosted sugar cookie bars serves a unique purpose. Here’s a closer look:

Dry Ingredients

• All-Purpose Flour
  The core component, flour provides structure, holding the bars together as they bake.
• Cornstarch
  Adds tenderness, preventing the bars from becoming tough. You’ll notice the difference in crumb.
• Baking Powder
  Helps the bars rise gently, resulting in a softer, fluffier texture.
• Salt
  Balances sweetness and enhances the buttery flavors.

Wet Ingredients and Sweeteners

• Unsalted Butter
  Supplies richness and moisture. For both dough and frosting, use unsalted butter for total control over salt content.
• Granulated Sugar
  Sweetens the dough and aids in creaming, giving the bars their signature lightness.
• Eggs and Yolks
  Offer structure, moisture, and help bind everything together.
• Sour Cream
  Adds a gentle tang while keeping the texture ultra-soft and tender.
• Vanilla Extract
  Provides warmth and depth; real extract shines through in both the bars and the frosting.
• Almond Extract (Optional)
  A few drops—it’s potent—add a distinctive, bakery-style note.

Frosting Components

• Butter
  Whipped with powdered sugar for a velvety, spreadable base.
• Powdered Sugar
  Thickens and sweetens, yielding a smooth frosting.
• Vanilla & Salt
  Bring balance and nuance to the frosting flavor.
• Milk
  Adjusts consistency, turning thick frosting into something silky.
• Food Coloring (Optional)
  A few drops instantly transform the look.
• Sprinkles
  Add a pop of color and a hint of crunch.

Ingredient Table

Step-By-Step Method: From Mixing to Frosting

1. Prepare Your Pan and Oven

Start with a 9×13-inch baking pan. For stress-free removal, line the pan with parchment paper, letting it overhang for easy lifting. Preheat your oven to 350°F (175°C).

2. Combine Dry Ingredients

In a medium bowl, whisk together flour, cornstarch, baking powder, and salt. Mixing dry ingredients first ensures an even rise and texture throughout the bars.

3. Cream the Butter and Sugar

In a large mixing bowl, beat softened butter with granulated sugar until pale and fluffy—this usually takes 3 minutes using an electric mixer on medium speed. Creaming incorporates air, resulting in tender, light bars.

4. Add Eggs and Flavorings

Beat in the whole egg and the additional egg yolks, one at a time, followed by the sour cream, vanilla extract, and almond extract if using. Mix until just combined.

5. Blend Wet and Dry Mixtures

Switch to a spatula—overmixing dough develops gluten and can make bars tough. Stir the dry mix into the butter mixture, folding gently until a soft dough forms.

6. Press and Bake

Transfer dough to your prepared pan. Using clean hands—or a sheet of parchment over the dough and a measuring cup—press it evenly into the corners. An even layer bakes uniformly.

Bake for 15-20 minutes. Watch for the edges to turn a light golden color while the center stays pale. Do not overbake; the bars will firm up as they cool. Cool fully in the pan on a wire rack.

7. Make the Frosting

While the bars cool, make your frosting. Beat softened butter until creamy, then gradually add powdered sugar. Mix in vanilla extract and a pinch of salt. Add milk, a tablespoon at a time, until the frosting reaches a spreadable consistency. A few drops of gel food coloring create vibrant pastels that won’t thin your frosting.

8. Frost and Decorate

Spread the frosting over cooled bars. Immediately scatter sprinkles on top. If you wait, the frosting will crust and the sprinkles may not stick well.

9. Slice and Serve

Let the frosted bars sit 10-15 minutes for easy slicing. Use a sharp knife or bench scraper for clean squares.

Tips for Exceptional Sugar Cookie Bars

• Room Temperature Ingredients: Soft butter and eggs mix smoothly, creating an even dough and tender bar.
• Accurate Measuring: Spoon flour into the measuring cup (versus scooping) or weigh for best results. Too much flour equals dry bars.
• Even Pressing: For thick cookie bars, aim for an even layer throughout the pan.
• Frost After Cooling: Frosting warm bars melts the buttercream. Be patient, and your frosting will stay plush and smooth.
• Color and Sprinkles: Switch up colors for holidays or add themed sprinkles for birthdays and events.

Customization Ideas

• Mix-Ins: Fold in mini chocolate chips or rainbow sprinkles for additional bursts of flavor and color inside the bars.
• Citrus Twist: Substitute lemon or orange zest for almond extract for a zingy twist.
• Festive Flavors: Experiment with peppermint extract in winter or coconut extract in summer, then adjust your frosting color to match.

Storage and Make-Ahead Options

At Room Temperature

Store frosted bars in a single layer in an airtight container up to 2 days. Place parchment between layers if stacking.

Refrigeration

For longer freshness, refrigerate bars in a sealed container up to one week. Let them come to room temperature before serving for the best texture.

Freezing

Freeze unfrosted bars by wrapping tightly in plastic, then placing in a freezer bag or airtight container. They keep well for up to three months. Thaw uncovered at room temperature, frost, and add sprinkles.

Freezer Table

*Note: Frosting takes on extra moisture in the freezer and may lose its texture.

Troubleshooting: Common Questions

Why are my bars tough or dry?

This is often from overbaking or packing too much flour. Next time, check your oven early and measure flour with care.

Why did my frosting turn runny?

Too much milk or warm butter can thin frosting. Start with less liquid, and add more only as needed.

Can I double the recipe?

Absolutely. Use a larger sheet pan or bake two batches at once. Keep an eye on bake time as larger pans bake faster.

Frosted sugar cookie bars offer everything you love about sugar cookies, delivered in a convenient, satisfying form. One batch yields gorgeous, bakery-style bars—rich, aromatic, and melt-in-your-mouth soft, under a luscious creamy topping. Whether you serve these at your next gathering or keep them as a family favorite, you’ll find yourself coming back to this easy, versatile recipe time and again.