Tessa’s Recipe Rundown
Taste: Sweet, chocolaty, and buttery.
Texture: Insanely chewy and fudgy!
Ease: Super quick and easy to make.
Why You’ll Love This Recipe: Fun, delicious dessert to feed a crowd.
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These blondies are soft, chewy, buttery, and packed flavor. The irresistible twist? A thick layer of rich, fudgy chocolate in every bite.

The luscious, melt-in-your-mouth fudge filling is pure dessert magic. Each bite is decadently gooey – you won’t be able to stop at just one.
The best part? They’re super easy to make. No fancy techniques or ingredients – you don’t even need a mixer!

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Whether you serve them warm for a gooey, over-the-top experience, or let them cool for the ultimate chewy bite, one thing’s for sure: these bars won’t last long!

Sprinkle of Science
How to Make Fudge Stuffed Blondies
How to Make Chewy Fudge Stuffed Blondies
Measure your ingredients correctly! If you are not measuring your ingredients with a digital kitchen scale, you could accidentally be adding too much flour, causing hard, dry, or cakey blondies. Learn more about how to measure ingredients correctly here!
Also, be sure not to overbake your blondies. Even if they seem just slightly underdone in the center, remove the them from the oven. They’ll solidify more as they cool.
The Pan
These Fudge Stuffed Blondies are ultra-thick and rich, so it’s important to use a pan that conducts heat effectively, to ensure they cook through completely but remain gooey in the center, without leaving the center completely underbaked.
For that reason, I highly recommend using a light-colored aluminum baking pan. Glass or ceramic pans can’t conduct heat as well and may result in underbaked or gummy centers. Dark pans may overcook the blondies. Avoid those types of pans if possible. Learn more about Glass vs. Metal Baking Pans here.
Leftover Sweetened Condensed Milk
- If you can find it, grab a pouch of sweetened condensed milk instead of a can – they’re perfect for recipes like this! I found mine at Fry’s / Kroger, but they’re also available at Walmart, or easily available online here.
- If you buy a can of sweetened condensed milk, you can try my S’mores Fudge Bars with the leftovers!
- You can also freeze it for another use by placing it in an airtight container for up to 3 months.
Layering the Fudge Stuffed Blondies
We assemble these Fudge Stuffed Blondies by spreading half the blondie batter in the pan, then using our palms to flatten pieces of the chocolate fudge filling. This is placed evenly in the pan, then the remaining Blondie batter gets spread on top. Super easy!
How to Store Fudge Stuffed Blondies
Store cooled Fudge Stuffed Blondies inside an airtight container at room temperature for up to 3 days. Re-warm slices in the microwave for 10-15 seconds before serving, for a more gooey texture, if desired.
More Blondie Recipes You’ll Love:
- Blondies Recipe – thick, chewy classic recipe
- Raspberry Dark Chocolate Blondies
- Brown Butter Triple Chocolate Blondies
- Cookie Butter Stuffed Blondies

Fudge Stuffed Blondies
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Ingredients
For the fudge filling:
- 1 1/4 cups (213 grams) semisweet chocolate chips
- 1/3 cup (104 grams) sweetened condensed milk
- 1 tablespoon (14 grams) unsalted butter
For the blondies:
- 1 stick (113 grams) unsalted butter, melted
- 1 cup (200 grams) light brown sugar
- 1 large egg
- 1 teaspoon vanilla extract
- 1/8 teaspoon fine salt
- 1 cup (127 grams) all-purpose flour
Instructions
- Preheat the oven to 350°F. Line an 8 by 8-inch pan with foil or parchment. Spray with nonstick cooking spray.
Make the Filling:
- In a small saucepan set over low heat, combine the chocolate chips, condensed milk, and 1 tablespoon of butter. Heat, stirring often, until melted and smooth. Set aside to cool.
Make the Blondies:
- In a large bowl, stir together the melted butter and brown sugar. Stir in the egg and vanilla until smooth. Add in the salt and flour and stir until just combined. The mixture will be thick.
Assemble:
- Spread half of the blondie batter into the bottom of the prepared pan. Using your hands, pick up portions of the fudge filling, flatten with your palms, and top the batter with pieces of the flattened fudge evenly. Spread the remaining blondie batter over the fudge evenly to cover completely.
- Bake for 25 minutes, or until lightly golden on the outside but still fudgy and moist on the inside. It’s better to under-bake than over-bake here! Let cool completely before slicing and serving.
I made the same mistake as the last commenter I think. It should have been specified that step 2. is for the filling and step 3 is for the outer blondie. I added the stick of butter to the saucepan rather than the tablespoon
Hi Rene, thanks so much for the feedback! I’ve updated the recipe instructions so they’re easier to follow. I hope you give this recipe another try. Let us know how it goes if you do!
Am I the only one who had a blob of blondie batter on top of the fudge, totally unspreadable?
Seems like the proportions are way off. I weighed everything and the blondie part is not enough for my roughly 8×8 pan. It doesn’t spread, it just blobs on top of the fudge. Either I messed up or the blondie batter needs to be less thick, more pourable.
I am sure they’ll taste good, but I am afraid they’ll look like shit. I will stick to other recipes I’ve tried. This was my first recipe from this blog/IG. Not sure I will try more if a basic blondie recipe ends up like patchy, two-tone dog poop in a pan.
Hi Anita! Sorry to hear you had issues with this recipe! It sounds like the technique of getting the dough/batter to spread thin may be the issue. Try patting it between your palms to thin it out, and don’t worry if it doesn’t look perfect because it’ll smooth out a bit when baking. How did your baked blondies look and taste?