How to Make Brownie Christmas Trees from Box Mix

These fudgy Easy Christmas Tree Brownies start with a boxed brownie mix and transform into festive holiday treats. With just a few pantry ingredients and minimal time, you bake a pan of brownies, cut them into tree-shaped triangles, and decorate them with a smooth green buttercream and colorful sprinkles to make cheerful brownie Christmas trees.

Cookie season is here, but these brownies offer a fun twist for holiday baking. Because the base uses a boxed mix, you save time and can focus on the decorating—perfect for holiday parties, classroom treats, or a family baking activity. Kids love joining in to pipe frosting and add sprinkles, and adults appreciate how simple yet impressive the finished treats look.

Ingredients for Brownie Christmas Trees

• 1 box milk chocolate brownie mix plus the ingredients called for on the box (water, oil, eggs).
• 1 1/2 sticks (¾ cup) unsalted butter, softened for the buttercream.
• 3 cups powdered sugar to sweeten and thicken the frosting.
• 2–3 tablespoons whole milk to loosen the frosting to the right consistency.
• 1 teaspoon pure vanilla extract for flavor.
• Green gel food coloring to tint the buttercream.
• Christmas sprinkles or small candies to mimic tree lights and ornaments.

How to Make Christmas Tree Brownies

Follow the boxed brownie mix directions, then bake in a prepared 9×13-inch pan. Use a non-stick spray or line the pan with parchment for easy removal. After baking, allow the brownies to cool completely on a wire rack so they firm up and are easier to cut.

Pro tip: Cooling the pan on a wire rack encourages even air circulation and speeds cooling slightly. If you’re in a hurry, refrigerate the cooled pan for 15–20 minutes before cutting, but let them come closer to room temperature for best texture.

Once cooled, cut the brownies into triangles that resemble Christmas trees. A simple approach: cut the pan in half lengthwise, then slice each half into triangles. Remove the rounded corner pieces if you want cleaner triangular shapes—those make a tasty snack while you work.

Cutting tip: Wipe a sharp knife between cuts and lightly spray the blade with cooking spray so it glides smoothly through the brownies. A plastic knife can also make cleaner cuts for some people.

To make the buttercream, beat the softened butter until creamy. Gradually add powdered sugar and beat until light and fluffy. Add vanilla and 1–2 tablespoons of milk to reach a spreadable consistency. Add green gel food coloring a little at a time until you reach your desired shade. If the frosting becomes too thin, add more powdered sugar in small increments to thicken.

Fill a piping bag or a resealable plastic bag with the green buttercream and pipe a decorative squiggle across each triangle to mimic tree branches. Top with festive sprinkles or tiny candies to look like lights and ornaments. For a trunk, use a small pretzel stick, a piece of candy, or a short piece of a peppermint stick.

How to Cut the Christmas Tree Brownies

For neat triangles, plan your cuts before starting. Cool the pan at least an hour so the brownies set. Spray both sides of your knife with cooking spray and wipe clean between cuts for the smoothest slices. Don’t worry about perfection—rustic triangles are charming and still taste great.

Extra tip: If you prefer uniform shapes, lightly mark cut lines on the top of the cooled brownies with the tip of a knife before cutting all the way through.

How to Decorate Christmas Tree Brownie Bites

A small squiggle of buttercream with a handful of sprinkles is all you need to make adorable brownie trees. For variety, try crushed peppermint for a peppermint crunch, mini M&M’s for colored “ornaments,” or tiny star-shaped sprinkles to top each tree. Swap the frosting style to pipe garlands, or spread the buttercream for a more rustic look.

Tips for Success

• Use boxed brownies for speed and consistency; homemade batter works fine too if you prefer.
• Make the frosting from scratch for a fresher flavor, but store-bought frosting works in a pinch.
• Let kids decorate their own trees to make this a fun group activity.
• Keep a damp cloth handy to wipe your knife between cuts for clean slices.

Variations

Add chocolate chips to the brownie batter for extra richness, or use different candies and sprinkles to change the look and flavor. You can also adjust the buttercream color from bright to forest green depending on your aesthetic.

Make-Ahead and Storage

These brownies can be made up to three days ahead. Store undecorated triangles at room temperature in an airtight container for up to two days, or refrigerate for up to three days. If already decorated, keep them in a single layer in a sealed container at room temperature for 1–2 days or in the refrigerator for up to three days. Allow chilled brownies to come closer to room temperature before serving for the best texture and flavor.

Easy Brownie Christmas Trees from a Mix — Recipe Summary