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.

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Beyond fudgey deliciousness. Like you’ll need a nap after the fact.
I made these without the fudge middle and added candy toppings (sprinkles, m&ms, Reese’s, & Oreos) on top and it came out amazing! My question is if I wanted to use this Blondie recipe but do it in chocolate brownie form, is there anything should I change to the recipe or can I add either cocoa powder, melted chocolate, or?
Taste-wise, these are yummy. Easy to make also. My only reservation about these is that because the recipe does not use a full can of sweetened condensed milk, I end up throwing out the remainder of the 14 ounce can. I always feel a little wasteful doing that. Doubling the recipe and making a 9″ x 13″ pan would use up more of the can but it still would not use up the entire can. Other than that, I love the chewiness of the cookie so I will make these again.
Oh you don’t need to waste condensed milk they last quite a long time in the fridge, u could also just drizzle them on top of ur Blondies for extra stickyness lol. Or make more fudge to eat it up with spoon or something
I made these on 5/15/20 and its a simple and straightforward recipe. If you are going to make this, my only suggestion to you would be to DOUBLE the blondie part. I made as it is described and weighed it (482 grams!) so each layer could be even, but when it came time to cover the chocolate, the dough was not very spreadable and it was simply not enough. Otherwise, great recipe!!!
I made these today, and they tasted good. However the Blondie dough seemed to be about half the amount needed for an 8×8. I used barely half to cover the bottom and it was such a thin layer that it would hardly cover. Then there was a thick layer of fudge. The remaining Blondie dough didn’t really cover the top. I spread it SOO thin. I had tiny bits of fudge coming through. I probably wouldn’t make this one again, but I did like that it had minimal ingredients!
I fail the chocolate feeling, I think. It dissolves into two consistency: watery and gooey chocolate. Can you suggest me what’s wrong?
Thank you.
Can you suggest a way to incorporate Nutella into these?
You can always replace the fudge layer with Nutella!
Am I the only one who had trouble with this recipe?! I feel like saying to “pour” the “batter” is inaccurate as it comes out more like a cookie dough… So it’s more of a spread than pour. Went over the recipe 100 times to see if I missed anything and I didn’t. Let’s hope for the best!
That’s a good point, I’ll update the recipe to clarify! Hopefully they turned out tasty 🙂
I just made them and while the taste is great, the fell apart while transferring to a cooling rack.
I followed the recipe to a T. Is there anything I missed?
Hi, Paulina! This recipe doesn’t call for cooling using a rack. Also, if you line the pan with foil or parchment and leave an overhang, that helps to transfer the sheet of blondies to a cutting board without it breaking apart.
This chocolate cake I like, the formula you shared helped me a lot in processing this dish.
They look amazing!
I’d really love to give this a try, but it’s hard to come by condensed milk where I live. Is there a way to substitute it? Or do I have to live without these in my life?
Loved them. Taste kind of like a chocolate chip cookie. Doubled the recipe for 9 by 13 and it worked out great, Maybe just a little thick on the fudge.