Marbled Brownies

These brownies start as one batter that gets split in two. Half stays vanilla, half gets melted chocolate chips folded in, then one goes on top of the other and a knife dragged through creates those swirled, marbled ribbons. Six ingredients, one bowl, and a simple technique that looks way more impressive than the effort involved.

The base batter is essentially a blondie: butter, sugar, eggs, vanilla, and flour beaten until smooth. It’s rich, buttery, and works as the perfect canvas for the chocolate swirl. Splitting it means each bite has both flavors instead of being all one thing.

Melt the chocolate chips over very low heat and stir them in gently. Overheating chocolate makes it seize into a grainy clump. If you’re nervous about direct heat, a makeshift double boiler (a bowl set over simmering water) gives you more control.

Kitchen Tips

• Zigzag through both batters with just 3 or 4 passes of the knife. More than that and you blend the layers together instead of creating distinct marble swirls.
• Don’t lift the knife out of the batter while swirling. Dragging it continuously through creates smoother, more dramatic patterns.
• Cool the brownies completely before cutting. Warm marbled brownies tear and smear at the swirl lines. Cold brownies give you clean, photogenic squares.
• The brownies are done at 25 minutes even if the center looks slightly underset. They firm up as they cool, and overbaking turns them dry and cakey.

Variations

• Cream cheese marble: Blend softened cream cheese with sugar and an egg, then swirl that through the chocolate batter instead for a cheesecake-brownie hybrid.
• Peanut butter swirl: Replace the vanilla batter with a peanut butter batter (add peanut butter to the base) for a chocolate-peanut butter marble.