Peppermint Sugar Cookie Bars with Peppermint Frosting bring a cool mint crunch to a soft, buttery cookie base. A sugar cookie mix keeps the dough simple, and homemade buttercream gives the top a creamy finish. You press the dough into a pan instead of rolling or cutting individual cookies. Let the bars cool fully, then frost, slice and share.
Why I Love This Recipe
These bars fit the busy part of holiday baking. The cookie base comes together in a bowl, and the frosting needs only a few pantry ingredients. Red-and-white candy adds a festive finish without piping or food coloring.
- Less shaping: Press the whole batch into a square pan.
- Two textures: A tender cookie layer meets smooth frosting and crunchy candy.
- Easy portions: Cut small squares for a dessert spread or pack them individually.
- Balanced mint: Peppermint extract flavors the frosting while candy adds little minty pockets to the base.
What You’ll Need
- Servings: 16 square bars
- Prep Time: 20 minutes
- Cook Time: 22–27 minutes
- Cooling and Setting Time: About 90 minutes
- Total Time: About 2 hours 12 minutes to 2 hours 17 minutes
- Oven Temperature: 375°F (190°C)
- Pan: 9×9-inch light metal baking pan
For the cookie base
- 1 package (17.5 ounces / 496 g) sugar cookie mix, a variety calling for butter and egg
- 1/2 cup (113 g) unsalted butter, softened
- 1 large egg, room temperature
- 1/2 cup (about 80 g) finely crushed peppermint candy canes
For the peppermint frosting
- 1/2 cup (113 g) unsalted butter, softened
- 2 cups (240 g) powdered sugar
- 2 tablespoons (30 ml) whole milk
- 1/2 teaspoon peppermint extract
- 1/8 teaspoon fine salt
- 3 tablespoons (about 30 g) crushed peppermint candy canes, for the top
Choose peppermint extract rather than a general mint blend. Crush the candy into small chips and crumbs, not large sharp chunks. Use the listed butter and egg amounts with a compatible mix; mixes that require different additions may give a different texture.
Tools You Need
- 9×9-inch light metal baking pan
- Parchment paper
- Large and medium mixing bowls
- Electric hand mixer
- Flexible spatula and offset spatula
- Measuring cups, spoons and kitchen scale
- Zip-top bag and rolling pin for crushing candy
- Wire cooling rack
- Sharp knife for portioning
How to Make Peppermint Sugar Cookie Bars with Peppermint Frosting
Keep the butter soft enough to dent with a finger, but still cool and solid.
Step 1: Mix the Cookie Dough
Heat the oven to 375°F (190°C). Line a 9×9-inch light metal baking pan with parchment, leaving overhang on opposite sides.
Combine 1 package (17.5 ounces) sugar cookie mix, 1/2 cup softened unsalted butter and 1 large egg in a large bowl. Mix just until no dry patches remain.
Fold in 1/2 cup finely crushed peppermint candy canes. Stop when the pieces are evenly spread through the thick dough.
Step 2: Press into the Pan
Transfer all the dough to the lined pan.
Press it into the corners and smooth the top to an even thickness. Use the back of a spatula or a small piece of parchment to prevent sticking.
Step 3: Bake and Cool
Bake for 22–27 minutes, checking at 22 minutes. The edges should look lightly golden, and the center should look set rather than wet. A toothpick near the center may carry soft crumbs, but should not have raw dough on it.
Place the pan on a cooling rack and cool completely, about 60 minutes. Allow longer if the bottom of the pan still feels warm. Leave the base in its pan for frosting.
Step 4: Beat the Peppermint Frosting
Beat 1/2 cup softened unsalted butter in a medium bowl for 1 minute, until creamy.
Add 2 cups powdered sugar, 2 tablespoons whole milk, 1/2 teaspoon peppermint extract and 1/8 teaspoon fine salt. Start on low so the sugar stays in the bowl.
Beat for 2–3 minutes, scraping the bowl as needed, until smooth and spreadable. The frosting should hold soft ridges rather than run off a spatula.
Step 5: Frost and Add the Candy
Spread all the peppermint frosting over the completely cooled cookie base, reaching the corners in an even layer.
Scatter 3 tablespoons crushed peppermint candy canes over the frosting. Press very lightly so the pieces cling without flattening the frosting.
Let the frosting settle for 30 minutes in a cool room before slicing. For make-ahead bars, hold back this topping until serving day for the best crunch.
Step 6: Slice and Serve
Lift the cooled, frosted slab out using the parchment overhang and set it on a cutting board.
Cut into 16 squares, making four rows in each direction. Wipe the knife between cuts to keep frosting from dragging across the edges.
Serve the bars on their own. If refrigerated, let them stand for 15–20 minutes before serving so the buttercream and cookie base soften slightly.
Why This Recipe Works (Quick Science)
Butter keeps the cookie crumb tender, while the egg helps the dough hold together after baking. Pressing the dough evenly prevents thin, dry edges and a thick, underdone middle. Stop baking once the center sets; a deep brown top usually means a firmer bar after cooling.
The candy behaves differently in each layer. Pieces in the dough soften during baking and leave minty flecks and small chewy pockets. Candy added after frosting stays crunchy at first. It slowly draws in moisture from the buttercream, which is why adding the topping close to serving gives the crispest finish.
Powdered sugar helps the buttercream hold its shape. Cooling the base first protects that structure: a warm cookie slab can melt the butter and make the frosting slide.
Common Mistakes to Avoid
- Using melted butter: It changes the dough’s texture and makes frosting too loose.
- Overbaking for a dark top: Look for set dough and pale golden edges instead.
- Frosting a warm base: Check the pan underneath before spreading the buttercream.
- Leaving large candy chunks: Small pieces are easier to slice and more pleasant to eat.
- Adding extra extract by eye: Measure it; a small excess can overpower the butter flavor.
Pro Tips
Let the parchment overhang act as handles, but support the slab underneath when lifting. For cleaner cuts, briefly chill the frosted slab until the top feels a little firmer. Avoid long uncovered chilling, which can dry out the cookie edges.
Make-Ahead and Storage
Keep the bars airtight in a cool room for up to 2 days, or refrigerate for up to 5 days. In a warm kitchen, use the refrigerator. Store in a single layer where possible to protect the frosting.
Freeze individual bars on a lined board until firm, then wrap and place in a freezer container for up to 2 months. Thaw covered in the refrigerator. Candy may turn tacky after freezing, so freeze without the candy topping when planning ahead, then add the reserved topping after thawing.
Macros Information
Estimated per bar, based on 16 equal portions. Values vary with the cookie mix and candy brand.
- Calories: 285 kcal
- Protein: 2 g
- Carbohydrates: 41 g
- Fat: 13 g
- Saturated Fat: 8 g
- Fiber: 0 g
- Sugar: 30 g
- Sodium: 130 mg
Frequently Asked Questions (FAQ)
Q: Can I use refrigerated sugar cookie dough?
A: It is not a direct swap for dry mix. The dough already contains fat and moisture, so adding the listed butter and egg would upset the balance. Use a recipe written for refrigerated dough instead.
Q: Does peppermint extract go in the cookie base too?
A: No. This version gets mint in the base from crushed candy. The measured extract goes into the frosting.
Q: Can I use starlight mints?
A: Yes. Choose red-and-white peppermint hard candies and crush them finely. Weigh them to match the candy amounts listed.
Q: Why is my frosting yellowish?
A: Butter naturally gives buttercream a slight ivory tone. Beat it until smooth and fluffy; you do not need food coloring.
Q: Why did the candy topping become sticky?
A: Hard candy absorbs moisture from the frosting and the air. Add the topping near serving time and keep the bars covered in a cool place.
Q: Can I bake these in a 9×13-inch pan?
A: A single batch would be much thinner and bake faster. Use the stated 9×9-inch pan for the intended thickness and timing.
Q: How do I know the middle is baked?
A: Look for a set surface without a shiny raw patch. A toothpick should show a few soft crumbs rather than sticky raw dough.
Q: Can I make the frosting ahead?
A: Yes. Refrigerate it airtight for up to 3 days. Let it soften, then beat briefly before spreading it over the cooled base.
Final Thoughts
Peppermint Sugar Cookie Bars with Peppermint Frosting make a cheerful holiday dessert with very little shaping work. Keep the base tender, wait for it to cool, and finish with a fresh sprinkle of candy. Leave a comment and share how your bars turned out. Happy cooking!