An old-fashioned sheet cake with great chocolate flavor. The top layer is crackly outside but remains gooey and rather soft inside. It keeps well and is perfect for potlucks, casual parties, or when you simply crave chocolate! Have it slightly underbaked for a fudgier experience.

Gooey and irresistible
I think this is one of the most sinful chocolate cakes ever. So we eat it regularly, lol.
It's great to snack on during long, festive weekends, to bake when you have kids and teenagers at home, and to take to a barbecue or potluck.
A crowd-pleaser like you wouldn't believe it. Or maybe you would. Some say it's the best chocolate cake I make. That's debatable because, you know, we already have the chocolate bourbon cake in the archives. But still.
It appeals to everyone, comes together really quickly, and has that magic ingredient that is condensed milk. Really, what recipe that has condensed milk isn't great? I dare you. I can give enough proof of this with the margarita key lime pie, the best chocolate fudge EVER, and my favorite sweet potato pie. The proof is in the pudding, definitively.
The frosting alone can be eaten with a spoon; that's how incredibly yummy it is.

Ingredient list
- Cocoa powder: always use unsweetened cocoa powder.
- Sweetened condensed milk: it's a must ingredient and can't be substituted. Use the regular type, not unsweetened or evaporated milk.
- Brown sugar: it makes a subtle difference in flavor and moistness, but you can use regular white sugar if that's all you have.
- Unsalted butter.
- Eggs: fresh, large.
- Powdered sugar: also called icing sugar or confectioners' sugar, is powder-like and needs to create that crackly top.
- Flour: both all-purpose and cake flour work well for this recipe.
- Salt.
- Vanilla extract.
- Ground cinnamon.
Quantities are listed in the recipe card towards the end of this post. The Ingredients page has more details and lists the brands we use.

How to make this cake
- Stovetop: the first step takes place on the stove, where you need to mix butter with cocoa and water. Remove when it breaks into a boil. This will ensure the cocoa dissolves well and 'blooms' which means the flavor will be deeper.
- Dry ingredients: they need to be sifted. Do so in a large bowl where you'll be mixing the chocolate batter.
- Condensed milk: you'll be using a whole can, but it will be divided. You'll use ⅓ of the can for the cake batter and the rest for the chocolate glaze. I eyeball it, but if you're uncomfortable doing that, you can measure or weigh it first and divide it accordingly.
- Final batter: it's quite thin, so I recommend you pour it into the prepared pan near the oven.


The sweetened condensed milk frosting
It's essential to make this such a decadent chocolate cake recipe.
The frosting or icing should be sweet, crackly, and with enough chocolate flavor. This one checks all the boxes, of course. That's why we love it so much.
Variation: sprinkle some chopped walnuts on the icing after you pour it over the hot cake.
Step-by-step VIDEO

Kitchen notes
- Organization: read the recipe first and ensure you have ingredients at the correct temperature, utensils and equipment needed, and enough workspace. This will make the process so much easier.
- Baking time: consider that all ovens and pans are different, even if they look similar. The baking time in my recipes is as accurate as possible, but it might take you more or less time. You can use a thermometer (like the OXO oven thermometer) to check that your oven is at the right temperature. I recommend tracking how your oven works and what tiny details you might need to adjust.
- Icing or glaze: always pour it over the warm cake so it seeps a little into the top of the cake. Or make a poke cake: pierce or poke holes with a brochette stick or toothpick on the surface of the cake when it comes out of the oven. Then pour the chocolate icing over them. It will seep more into the baked cake and the whole thing will be fudgier.
- Cake pan: I use a rectangular pan without a removable bottom and serve the cake straight from the pan. This is because when you pour the frosting some of it goes to the sides, and spills down the bottom sometimes. But you can use a pan with removable bottom, refrigerate the cake after you glaze it and then remove it before serving.
- Fudgier cake: if you slightly underbake the cake, it will be fudgier. And even more amazing in my opinion!
- Walnuts: sometimes, I sprinkle chopped walnuts on top of the icing before it sets.
- Serving it: I like it as is, straight from the pan. But you can recreate the so-called 'better than sex cake' by adding a thick layer of whipped cream (or cool whip topping), drizzling caramel sauce or dulce de leche over it, and adding chopped heath bars or toffee bits on top. A decadent dessert for those with a sweet tooth!
- Variation: for a more sophisticated version, add a tablespoon of your favorite liquor (I love Kahlua, Baileys, and Cointreau) to the batter and the icing. Or whisky/bourbon; it works so well with chocolate. Did I tell you about my favorite cake, the Bourbon Hot Chocolate Bundt Cake? It's beyond amazing.

Related recipes you might like:
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Gooey Chocolate Sheet Cake (with condensed milk)
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Ingredients
For the cake:
- 1 cup unsalted butter
- ½ cup unsweetened cocoa powder
- 1 cup water
- 2 cups all-purpose flour, or cake flour
- 1 teaspoon baking soda
- 1 teaspoon cinnamon
- ½ teaspoon salt
- 1 ½ cups brown sugar, light or dark, firmly packed
- 1 can sweetened condensed milk, 14 ounces or 397g, divided
- 2 eggs, at room temperature
- 1 teaspoon vanilla extract
For the frosting:
- ¼ cup butter
- 2 tablespoons unsweetened cocoa powder
- 1 cup powdered sugar, also known as icing sugar or confectioners' sugar
Instructions
- Preheat the oven to 350ºF (180°C).
- Grease a 13x18-inch (33x45cm) pan. I serve it directly from the pan or cake tin, but if you want to remove it and serve it on a platter, you can line the sheet pan with a piece of parchment paper. See Notes below.
For the cake:
- Melt 1 cup unsalted butter in a small saucepan.
- Add ½ cup unsweetened cocoa powder and 1 cup water and bring to a boil. Remove from heat.
- Sift 2 cups all-purpose flour, 1 teaspoon baking soda, 1 teaspoon cinnamon and ½ teaspoon salt in a large mixing bowl. Add 1 ½ cups brown sugar and combine.
- Make a well in the center and add the cocoa mixture, ⅓ can (eyeball it) of the condensed milk, 2 eggs and 1 teaspoon vanilla extract. Mix until the batter is smooth.
- Pour into the prepared pan and bake for about 20 minutes, until the cake springs back and a cake tester or toothpick inserted in the center comes out with some moist crumbs attached. It should not come out wet. Don't overbake it. This is not a very tall cake so it doesn't take long to bake. But all ovens are different so check to see if it's done.
For the frosting:
- Have it ready before the cake comes out of the oven.
- Melt ¼ cup butter in a small saucepan (I use the same one as before without cleaning it).
- Remove from the heat and add 2 tablespoons unsweetened cocoa powder and the rest of the condensed milk. Mix well.
- Add 1 cup powdered sugar and mix until completely smooth.
- Spread over the warm chocolate cake as it comes out of the oven. You can poke holes with a toothpick or brochette stick so it seeps deeper.
- Let cool completely. If removing it from the pan, refrigerate it first just until firm so it's easier to remove.
- Refrigerate leftovers, well covered in plastic wrap or in an airtight container.
Notes
Cocoa powder: always use unsweetened cocoa powder. In my experience, the dark ones are the best (this does not apply to the super dark used for making homemade oreo cookies known as 'dark or black cocoa powder'). Sweetened condensed milk: it's a must ingredient and can't be substituted. Use the regular type, NOT unsweetened or evaporated milk.
gale bygrave says
can you tell me if the flour is self raising or plain flour please?
Paula Montenegro says
It's all-purpose flour. You can also use cake flour. Unless specified, I never use self-rising.
Pinky says
Came out great! I did replace the water with a 1/2 cup of strong brewed coffee and 1/2 cup of Kahlua. Yum!
Pam says
Where is the recipe for the frosting? Could you please send it to me?
Thank you
Phanson56@icloud.com
Paula Montenegro says
Hi Pam, it is explained in the whole recipe. But, to make it easier, I divided it into two parts. Have a great week.
Andrea_TheKitchenLioness says
Paula, "Vintage Mondays" sounds like a wonderful idea to me - I am making a mental note to not forget to check for your Monday posts in particular! Having said that, your "Vintage" cake recipe looks like pure sweet comfort food, delicious!
Katie says
This cake looks so moist! The crackly top reminds me of a brownie. I need a piece of this STAT. 🙂
everydaymaven says
I love this! My mom collects cookbooks and has amassed quites the library. she has some awesome vintage ones with pages falling out. I should revisit them for inspiration!
Carol | a cup of mascarpone says
OMG…this looks incredible, Paula!!! I'm so happy to hear we will be able to be given some of your vintage recipes. I can't wait!
thelittleloaf says
Love love love the look of that crackly crunchy topping. Yum!
kelly @ kellybakes says
I'm so glad I found your blog! I love gooey, fudgy brownies. They remind me of ones I used to help my dad make as a kid. I also love old cookbooks--in fact my dad just gave me a bunch of his and I love reading the titles of recipes and the instructions to see how they differ. Have you ever read any old cake decorating magazines or books? I have a bunch and the designs are simultaneously awesome in their intricacy as well as their gaudiness. It's impressive!
e / dig in says
I'm reading this on tuesday and all that chocolateness looks a good as it did on vintage monday 🙂
yummychunklet says
Looks gooey and delicious!
RavieNomNoms says
Oh my goodness that almost looks like a brownie it is so rich!
Matthew 'mmWine' Horbund says
Robin and I love vintage cookbooks as well. Sadly, we don't have a big collection. We'll have to get more to find delicious recipes like this!
CJ says
Excellent cake that everybody would love.
Guru Uru says
That looks so moist, Fudgy and delicious 😀
Cheers
Choc Chip Uru
Alice Choi says
Paula, love this! Now, will you eat this cake? 😛
Julia says
Paula, this looks amazing. I will be trying it, but with pecans, sometime soon.
Baker Street says
You're on a roll, Paula! Absolutely loving the gooey chocolate cake filled with nuts! Simply delicious.
cquek says
OMG – simply gorgeous. Your styling is exquisite…!
Medeja says
Gorgeous cake!
And seems like you have many great things lined up, hope to see them soon on your blog! 🙂