Introduction

Chocolate Swiss Meringue Buttercream is a silky, rich frosting that’s perfect for cakes and cupcakes. It combines the lightness of meringue with the lusciousness of chocolate and butter, creating a smooth and fluffy texture that melts in your mouth.

A close-up top view of thick, creamy chocolate frosting swirled smoothly in a white bowl with a speckled pattern along the rim. The frosting has a rich brown color with soft peaks and ridges, showing a glossy texture that catches the light. The background is a white marbled surface. Photo taken with an iphone --ar 4:5 --v 7

Ingredients

2/3 cup (133 grams) granulated sugar
4 large egg whites*
1/4 teaspoon fine sea salt
3 sticks (340 grams) unsalted butter, cut into 12 pieces and at room temperature
12 ounces (340 grams) semisweet chocolate, melted and cooled to room temperature
1 teaspoon vanilla extract

Instructions

Step 1: Combine the sugar, egg whites, and salt in the bowl of a stand mixer. Set the bowl over a saucepan filled with 1-inch of gently simmering water. Whisk gently and constantly until the sugar dissolves, the mixture thickens slightly, becomes foamy, and reaches 160°F on a candy or digital thermometer, about 3 minutes. Remove from heat and wipe the bottom of the bowl dry.
Step 2: Attach the bowl to the mixer with the whisk attachment and whip until the meringue is thick, glossy, and stiff peaks form. The bowl should no longer feel warm to the touch, which usually takes 7 to 10 minutes.
Step 3: Switch to the paddle attachment and, with the mixer on low speed, add the butter cubes one at a time, incorporating each fully before adding the next. Continue beating until the mixture reaches a silky smooth texture; this may take several minutes.
Step 4: If the buttercream curdles, keep mixing—it will come back together. If it becomes too thin or runny, refrigerate for about 15 minutes, then continue mixing until it smooths out.
Step 5: Add the cooled melted chocolate and vanilla extract, mixing until combined. Increase the speed to medium-high and beat until the buttercream is light, fluffy, and well combined, about 30 seconds. Scrape down the sides and bottom of the bowl as needed.

Tips & Variations

Ensure your butter is at room temperature to prevent curdling and achieve a smooth texture.
If your buttercream becomes runny, chilling slightly and then continuing to mix can help it firm up.
Use high-quality semisweet chocolate for the best flavor balance.
For a different twist, try swapping the semisweet chocolate for milk or dark chocolate.

Storage

Store the buttercream in an airtight container in the refrigerator for up to 5 days or freeze it for up to 2 months. Before using, allow it to come to room temperature and beat on low with the paddle attachment until creamy. If it appears runny or curdled, microwave about 1/4 cup for 5-10 seconds, then mix back into the bowl and beat on medium-high until smooth.

How to Serve

A close-up image of a bowl filled with smooth, thick chocolate frosting that has been freshly mixed, showing swirls and soft peaks with a glossy texture. The chocolate is dark brown with tiny air bubbles scattered throughout, and the frosting looks rich and creamy, covering most of the inside of the bowl evenly with visible ridges and curls made by mixing. Photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use pasteurized egg whites for this recipe?

Yes, pasteurized egg whites are safe and work well for making Swiss meringue buttercream, especially if you want to avoid raw egg concerns.

What can I do if my buttercream is grainy or not smooth?

This often happens if the sugar hasn’t fully dissolved or if the butter isn’t properly softened. Make sure to heat the meringue mixture until smooth and use room temperature butter. Continue mixing patiently, and the texture will become silky.