Fudgy KitKat Blondies – Deliciously thick and fudgy blondies that are stuffed with whole KitKats. The ULTIMATE blondie recipe!

Fudgy KitKat Blondies
Today’s recipe is a take on my Fudgy KitKat Brownies that you guys have been loving. Let me introduce to you the BEST blondies you’ll ever make – Fudgy KitKat Blondies!
These blondies are incredibly thick and fudgy, made with all-brown sugar for a rich caramelized flavour, and stuffed full of whole KitKat bars.
Are you a fan of blondies and KitKats? Got a big sweet tooth? Then you are gonna love this blondie recipe.
Looking for more blondie recipes? See my Chocolate Chip Blondies, Chocolate Peanut Butter Blondies, and my Carrot Cake Blondies.
Ingredients you’ll need
Here’s a list of ingredients you’ll need to make these blondies. You can find my recipe card at the bottom of this post for the complete list with their amounts.
- Unsalted butter
- Light brown sugar: Using all brown sugar makes for extra fudgy blondies that have a rich caramelized flavour.
- Large egg + an egg yolk: An extra egg yolk makes for more chewier, fudgy blondies.
- Vanilla extract
- Plain/all-purpose flour
- Salt
- KitKats: You’ll need 16 2-finger KitKat bars, or 8 4-finger bars.
How to make Fudgy KitKat Blondies
To make these blondies, simply start by whisking together the butter and sugar until combined. Add the egg, egg yolk, and vanilla, and whisk until smooth and combined.
Add the flour and salt, and whisk until completely combined.
Spoon half of the batter into an 8×8-inch square baking pan lined with parchment paper. Place the whole KitKat bars on top, then spoon the remaining batter over the KitKats, spreading out evenly. Sprinkle with crushed KitKat bars.
Bake for 35 – 40 minutes, or until the edges are browned and the centre is no longer jiggly – just set.
Allow to cool completely in the pan on a wire rack before cutting into squares.
The printable recipe card with the FULL list of ingredients and instructions can be found at the bottom of this post.
NOTE: For best results, I highly recommend using the gram measurements (with a digital scale), rather than the cup measurements.
Cup measurements are simply not accurate enough, and I cannot guarantee the best results if you use them.
These Fudgy KitKat Blondies are:
- super quick and easy to throw together
- deliciously chewy and fudgy
- infused with vanilla and have a deep caramelized flavour
- LOADED with whole KitKat bars
How long will these blondies last? These blondies can be stored in an airtight container at room temperature or in the fridge for up to 1 week.
Can I freeze these blondies? Yes, they also freeze well for up to 3 months. Thaw overnight in the fridge before serving.
If you try this recipe, let us know! Leave a comment, rate it, and don’t forget to tag me on Instagram and hashtag it #simplybakeblog. I’d love to see!
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Fudgy KitKat Blondies
Deliciously thick and fudgy blondies that are stuffed with whole KitKats. The ULTIMATE blondie recipe!
Ingredients
- 3/4 cup (170g) unsalted butter, melted
- 1 and 1/2 cups (300g) light brown sugar
- 1 large egg + 1 egg yolk
- 2 teaspoons vanilla extract
- 1 and 1/2 cups (190g) plain/all-purpose flour
- 1/4 teaspoon salt
- 16 2-finger KitKat bars (or 8 4-finger bars), 4 bars crushed, 12 left whole
Instructions
- Preheat the oven to 180C/350F/Gas 4. Line an 8x8-inch square baking pan with foil or parchment paper. Set aside.
- In a large bowl, whisk together the butter and sugar until combined. Add the egg, egg yolk, and vanilla, and whisk until smooth and combined.
- Add the flour and salt, and whisk until completely combined.
- Spoon half of the batter into the prepared pan. Place the whole KitKat bars on top, then spoon the remaining batter over the KitKats, spreading out evenly. Sprinkle with the crushed KitKat bars.
- Bake for 35 - 40 minutes, or until the edges are browned and the centre is no longer jiggly - just set.
- Allow to cool completely in the pan on a wire rack before cutting into squares.
Notes
Blondies can be stored in an airtight container at room temperature or in the fridge for up to 1 week. They also freeze well for up to 3 months. Thaw overnight in the fridge before serving.
Nutrition Information:
Yield:
16 barsServing Size:
1 barAmount Per Serving: Calories: 162Total Fat: 11gSaturated Fat: 6gTrans Fat: 0gUnsaturated Fat: 3gCholesterol: 47mgSodium: 45mgCarbohydrates: 15gFiber: 0gSugar: 8gProtein: 2g
Nutrition information isn’t always accurate.
S
Sunday 26th of April 2020
Tried this and they couldn’t have been more cakey if I tried they were not Fudgy at all. Followed exact measurements and even cooked for less time too! Not sure where it went wrong.
Demeter
Monday 1st of July 2019
Ooh what a fun recipe! It's always such a treat to add some candy into baked goods. :)
ANNE
Sunday 30th of June 2019
CAN I JUST ASK IS IT A FAN OVEN YOU USE FOR ALL YOUR RECIPES?
Marsha
Sunday 30th of June 2019
Yes, I have a fan-assisted oven.