These chocolate mint brownies feature three irresistible layers: a fudgy brownie base, a creamy mint frosting, and a smooth chocolate topping. Made from scratch, they’re the perfect mint-chocolate treat.
Updated March 12, 2025 with new photos and a slightly adjusted recipe to keep the brownies decadent but a bit less rich than the original version.
Mint brownies are rich, fudgy, and surprisingly simple to assemble. The deep chocolate of the brownie layer balances perfectly with the bright mint filling and a glossy chocolate finish. While this recipe has three components, none of them are complicated—just a little extra time and patience for cooling and layering. If you’re short on time you could use boxed brownie mix for the base, but the scratch version yields the best texture and flavor.
Chocolate Mint Brownies = 3 Layers of Deliciousness
Brownie Layer
For a fudgy, chewy brownie that still holds up under frosting, this recipe uses both cocoa powder and melted semi-sweet chocolate. The flour amount is kept moderate so the crumb is dense and chewy rather than cake-like or overly gooey—important when you plan to add two more layers on top.
Mint Frosting
The mint layer is a thick buttercream-style filling. It’s intentionally sweet to contrast the bittersweet chocolate. Peppermint extract provides the mint flavor—start with a modest amount and taste as you go; 1 1/2 teaspoons is a good guideline if you like a noticeable but not overpowering mint. The filling spreads thinly over the brownies, which is fine because a chocolate layer covers it.
Chocolate Topping
The top layer is made by melting chocolate with butter so the ganache is creamy and sets smooth for clean slices. Semi-sweet or 50% dark chocolate works best; avoid very high-percentage dark chocolate (above ~60%) for this topping or it can be too firm and bitter.
Recipe Tip
Each layer must be completely cool and set before adding the next. Cool the baked brownies fully before making and spreading the mint filling. Chill the frosted brownies at least 20 minutes before pouring the chocolate topping. After adding the ganache, refrigerate until the chocolate is firm for the cleanest slices.
Can I use Brownie Mix to Make Mint Brownies?
Yes. If you prefer a shortcut, use a boxed brownie mix sized for a 9×13 inch pan, bake according to package directions, then proceed with the mint filling and chocolate topping described here.
Freezing Brownies
To freeze: bake and cool the brownie base to room temperature, wrap tightly, and freeze for up to 3 months. Thaw overnight in the refrigerator, then add the mint filling and ganache just before serving for best texture and flavor.
If you enjoy mint and chocolate together, these brownies are a great addition to your baking repertoire. They also pair well with other mint-chocolate desserts or with a simple scoop of vanilla ice cream when serving.
Mint Brownies
Equipment
- 9×13 inch (23 x 33 cm) baking pan*
Ingredients
Brownie Layer
- 1 cup unsalted butter (226 grams)
- 4 oz semi-sweet chocolate (112 grams) or 50–70% dark chocolate
- 2 cups white sugar (400 grams)
- 4 large eggs, room temperature
- 1/4 cup cocoa powder (22 grams)
- 1 cup all-purpose flour (125 grams)
- 1/2 teaspoon salt
Mint Frosting
- 1/2 cup unsalted butter (112 grams), softened
- 2–4 drops green food coloring
- 1 1/2 teaspoons peppermint extract, to taste
- 1/4 teaspoon salt
- 2–2 1/2 cups powdered sugar (220–275 grams)
- 1–2 tablespoons heavy cream (or whipping cream or milk) as needed
Chocolate Topping
- 6 oz semi-sweet chocolate (about 3/4 cup or 170 grams)
- 1/2 cup unsalted butter (112 grams)
Instructions
Brownies
- Preheat oven to 350°F (175°C).
- Line a 9×13 inch pan with parchment paper leaving an overhang, or lightly grease the pan.
- Place butter and chocolate in a heatproof bowl. Microwave on medium power for 60 seconds, stir, and repeat in short bursts until smooth. Let cool slightly.
- Whisk the sugar into the chocolate mixture, then whisk in the eggs until combined.
- Sift in the cocoa powder, flour, and salt. Whisk until the batter is smooth with no visible streaks of flour.
- Pour into the prepared pan and bake 25–30 minutes, until the top is set and a toothpick comes out clean or with a few moist crumbs but no raw batter.
- Cool the brownies completely in the pan before adding the next layer.
Mint Filling
- Beat the softened butter in a large bowl until fluffy.
- Add 1 teaspoon peppermint extract, a few drops of food coloring, the salt, and 2 cups powdered sugar. Start mixing on low speed and increase as needed.
- Add heavy cream 1 tablespoon at a time to reach the desired consistency.
- Taste and adjust peppermint extract, coloring, powdered sugar, or cream as needed.
- Once the brownies are completely cooled, spread the mint frosting into an even layer using an offset spatula. It will be relatively thin—this is intentional. Chill the pan at least 20 minutes before adding the chocolate topping.
Chocolate Topping
- Chop the chocolate finely (if using bars) and place in a heatproof bowl with the cubed butter.
- Microwave on medium power for 45 seconds, stir, and continue in short bursts until smooth.
- Pour the warm chocolate over the chilled mint layer and spread evenly with a clean offset spatula.
- Refrigerate until the chocolate is set, about 30–60 minutes.
- When ready to slice, lift the brownies from the pan using the parchment overhang if used, place on a cutting board, and cut with a sharp knife, wiping the blade between slices for clean edges.
Notes
- Pan sizes: Halve the recipe for an 8×8 inch pan (bake time ~20–25 minutes); bars will be thinner.
- Serving: This recipe yields 18 large brownies or about 24 smaller pieces—24 is a good size for dessert trays.
- Storage: Store in an airtight container in the refrigerator for up to 5 days.
- Nutrition: Nutrition info is an estimate per brownie, calculated assuming 18 large servings.