Introduction

These Cinnamon Swirl Snickerdoodle Blondies are a delightful twist on classic blondies, featuring a warm cinnamon sugar swirl that adds a cozy, spiced touch. They’re soft, buttery, and perfect for any dessert craving.

The image shows four square pieces of cinnamon swirl blondies on a dark baking tray. Each blondie has two visible layers: a light golden-brown base layer with a soft cake-like texture and a darker brown cinnamon swirl on top, creating a marbled effect. The top layer looks slightly crumbly and sugar-coated, adding texture. In the background, another blondie and a white plate with wooden-handled cutlery rest on a white marbled surface. The warm lighting highlights the blondies' moist and crumbly quality. photo taken with an iphone --ar 4:5 --v 7

Ingredients

1 cup unsalted butter, melted and slightly cooled
1 1/4 cups light brown sugar, packed
1/2 cup granulated sugar
2 large eggs, room temperature
2 teaspoons vanilla extract
2 1/4 cups all-purpose flour
1 teaspoon cream of tartar
1/2 teaspoon baking soda
1/2 teaspoon salt
1/3 cup granulated sugar
1 tablespoon ground cinnamon
2 tablespoons unsalted butter, melted
2 tablespoons granulated sugar mixed with 1/2 teaspoon ground cinnamon (optional topping)

Instructions

Step 1: Preheat your oven to 350°F (175°C). Grease a 9×13-inch baking dish and line it with parchment paper, leaving an overhang on the sides for easy removal.
Step 2: In a large bowl, whisk together the melted butter, brown sugar, and granulated sugar until smooth. Add the eggs and vanilla extract, whisking until fully incorporated and the mixture is thick and glossy.
Step 3: In a separate bowl, sift together the flour, cream of tartar, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, stirring until just combined. Avoid overmixing to keep the blondies tender.
Step 4: For the cinnamon swirl, mix the 1/3 cup granulated sugar and 1 tablespoon ground cinnamon in a small bowl. Stir in the melted butter until the mixture resembles wet sand.
Step 5: Spread half of the blondie batter evenly into the prepared baking dish using a spatula. Sprinkle the cinnamon-sugar mixture over the batter, spreading it evenly. Dollop the remaining batter over the cinnamon layer and gently spread to cover. Use a butter knife to swirl by dragging it through the batter in a zigzag pattern.
Step 6: If desired, sprinkle the cinnamon-sugar topping evenly over the surface for an extra spiced crunch.
Step 7: Bake for 30–35 minutes, or until the edges are golden brown and a toothpick inserted into the center comes out with a few moist crumbs.
Step 8: Let the blondies cool in the pan for 20 minutes. Use the parchment paper overhang to lift them out, transfer to a cutting board, slice into squares, and serve.

Tips & Variations

For extra gooeyness, slightly underbake the blondies and let them finish setting as they cool.
Swap cream of tartar with 1 teaspoon lemon juice or vinegar if unavailable; it helps create the snickerdoodle’s signature tang.
Add chopped nuts or white chocolate chips to the batter for a delightful texture contrast.
Use parchment paper with an overhang to easily lift blondies out without sticking or breaking.

Storage

Store cooled blondies in an airtight container at room temperature for up to 3 days. For longer storage, keep them in the refrigerator for up to a week. Reheat individual squares in the microwave for 10–15 seconds to enjoy warm, or serve at room temperature.

How to Serve

A close-up view of four square pieces of crumbly cinnamon swirl brownies arranged neatly on a dark baking tray, each piece showing two visible layers: a dense, rich chocolate base layer and a lighter, crumbly beige top layer with dark brown cinnamon swirls creating a marbled pattern, with a subtle powdered sugar dusting on top; the background shows a blurred white plate stacked with white napkins and wooden cutlery on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I use salted butter instead of unsalted?

Yes, but reduce the added salt to 1/4 teaspoon to prevent the blondies from becoming too salty.

How do I know when the blondies are done?

The edges should be golden brown and set, but the center will still have a few moist crumbs when tested with a toothpick. This ensures the blondies stay soft and chewy.