Easy Guinness Brownies

Why You'll Love This Recipe

If you love chocolate desserts with a grown-up twist, these brownies are for you.

Simple ingredients - Everything starts with a boxed brownie mix, so there's no complicated measuring or long ingredient list.

Easy to make with a brownie mix - These are easy Guinness brownies with cake mix, which means less prep and more time enjoying dessert.

Rich stout beer flavor inside and out - The Guinness Extra Stout goes into both the brownies and the frosting, giving these brownies a deep, rich flavor in every bite.

Perfect for St. Patrick's Day - These brownies are festive, fun, and guaranteed to disappear fast at any St. Patrick's Day gathering. Add some green sprinkles for a little extra colorful punch.

Ingredients and Their Part in the Brownies

This recipe keeps things simple while delivering big flavor. Here's what you'll need:

For the brownies:

• Brownie mix - The base that makes this recipe quick and foolproof.
• Guinness Extra Stout - Adds depth and enhances the chocolate flavor beautifully.
• Eggs - Provide structure and help create that perfect chewy texture.
• Oil - Keeps the brownies moist and tender.
• Butter - Adds richness and balances the stout flavor.

For the frosting:

• Unsalted butter - The creamy base for the frosting.
• Powdered sugar - Sweetens and thickens the buttercream.
• Salt - Balances the sweetness and enhances flavor.
• Vanilla extract - Adds warmth and rounds out the frosting.
• Guinness - Gives the frosting a subtle stout flavor that complements the brownies.

Ingredient note

I use Duncan Hines brownie mix that calls for ⅓ cup water and ½ cup oil. The amount of Guinness equals the water measurement, and the combination of ¼ cup butter and ¼ cup oil equals the oil amount listed on the box. If your brownie mix calls for different amounts of oil or water, adjust accordingly.

How to Make Guinness Brownies

These brownies come together quickly and bake up beautifully. Here's how to go about making them:

1. While preheating the oven to 350°F, combine all the brownie ingredients in a medium bowl.
2. Mix until just incorporated.
3. Pour batter into an 8x8-inch baking pan that has been sprayed with nonstick spray and lined with parchment paper. Leave extra parchment paper on the side to make the brownies easy to remove. Smooth top.
4. Bake for 30-34 minutes or until a toothpick in the center comes out clean. Let cool in pan.

For the frosting (totally optional but it adds the perfect sweetness)

1. In the bowl of a stand mixer, combine room temperature butter with powdered sugar, vanilla extract, salt, and 2 tablespoons Guinness.
2. Mix until creamy. If it is too dry, add additional tablespoon of Guinness, if it is too wet, add more powdered sugar.
3. When brownies are cool, lift out of baking pan with parchment paper handles. Spread with frosting.
4. When frosted, you can put them in the refrigerator for an hour or so to make them easier to cut, remove and cut into 16 squares.

These Guinness chocolate brownies with buttercream frosting are rich, super chocolatey, and totally satisfying without feeling too heavy. They're the perfect grown-up way to treat yourself when a serious chocolate craving hits.

Recipe Variations to Make Them Your Own

This recipe is easy to customize depending on your taste.

Add-ins - Stir in ½ cup chocolate chips or chopped pecans or walnuts. You can also substitute 1 to 2 tablespoons of Guinness with Irish whiskey for a stronger flavor.

Bailey's frosting - Use Baileys Irish Cream instead of Guinness in the frosting for a creamier flavor.

Irish whiskey frosting - Swap Guinness in the frosting for Jameson whiskey for a bold twist.

Decorate - Top with green sprinkles or shamrock decorations for a festive St. Patrick's Day look.

How to store the brownies and how long they last

Store brownies in an airtight container in the refrigerator for up to 1 week.

For longer storage, freeze them in a freezer-safe container for up to 3 months. Thaw in the refrigerator overnight before serving.

More Brownie Recipes

If you love brownies, there are so many delicious ways to switch things up.

• Chocolate Banana Pudding Brownies combine creamy pudding flavor with rich chocolate.
• Glazed Lemon Brownies are bright, sweet, and perfect for spring.
• Key Lime Cheesecake Brownies are a fun citrus twist on a classic.
• Loaded Chocolate Brownies are packed with candies and chocolatey goodness.
• Red Velvet Brownies are rich, colorful, and topped with cream cheese frosting.

Find lots of easy recipes for brownies and bars to make for any fun occasion right here on 2CM!