An old-fashioned sheet cake with great chocolate flavor and condensed milk, so you know it'll be scrumptious! The top layer is crackly on the outside but remains gooey and soft inside. You can slightly underbake it for a fudgier experience. It keeps well and is perfect for potlucks, casual parties, or when you crave a decadent chocolate dessert!
Gooey and irresistible
I think this is one of the most sinful chocolate cakes I've ever had. 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, is pretty easy to make, and has that magic ingredient, which is sweetened condensed milk. Really, find recipes with condensed milk that aren't great, I almost dare you.
And the frosting alone can be eaten with a spoon; that's how incredibly yummy it is.
Sweetened condensed milk cakes started showing up in mid-century cookbooks and newspaper clippings, especially as post-war convenience baking took off. Can't blame them.
Testing Notes
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 glaze, some of it spills over to the sides and sometimes down the bottom. However, you can use a pan with a removable bottom. Refrigerate the cake after you glaze it, then remove it before serving.
Brown sugar: It makes a subtle difference in flavor and moistness, but you can use regular white sugar if that's all you have.
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.
It's key to pour the icing over the warm cake so it seeps slightly into the top of the cake. If the cake is cold, it will not have the same effect.
For a fudgier cake, slightly underbake the cake. And even more amazing in my opinion!
Ingredients
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.
- Cocoa powder: always use unsweetened cocoa. 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.
- Powdered sugar: also called icing sugar or confectioners' sugar, it's needed to create that crackly top.
Process steps
Dry ingredients
Except for the cocoa powder, sift the dry ingredients in a large bowl that can accommodate all the chocolate batter.
Stovetop
The chocolate custard is cooked on the stove, where you need to mix butter with cocoa powder and water. Remove when it breaks into a boil. This will ensure the cocoa dissolves well and 'blooms', which deepens the flavor.
Cake batter
Both preparations above are then stirred together.
The final chocolate batter is quite thin, so I recommend you pour it into the prepared pan near the oven.
Icing step-by-step video
Chocolate icing
It's essential to make this a decadent chocolate cake recipe. The frosting or icing is sweet, crackly, and has a lot of chocolate flavor. That's why we love it so much.
Variation: sprinkle some chopped walnuts on the icing after you pour it over the hot cake.
Make the topping
It's unctuous and fluid. You'll want to eat it with a spoon, just saying!
Have it ready before you remove the cake from the oven.
Poke the surface
Immediately when it comes out of the oven, pierce or poke holes with a brochette stick or toothpick.
Final step
Pour the chocolate icing while the cake is still hot, or at least very warm. It will seep more into the baked cake, and the whole thing will be fudgier and moister.
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Gooey Chocolate Sheet Cake with Condensed Milk
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 usually serve it directly from the pan or cake tin, but if you want to remove it and serve it on a platter, use a cake pan with a removable bottom and line it with 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 the frosting over the warm chocolate cake as it comes out of the oven. Or make a poke cake: pierce or poke holes in the surface of the cake with a brochette stick or toothpick 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.
- 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').
Julie Forbes says
Sounds so delish but I’m totally confused about the way you line the tin for this cake? Julie
Paula Montenegro says
Hi Julie! The best way is to make a crisscross pattern with two pieces of parchment paper. They are placed in opposite directions and both cover the bottom and two of the sides. The angles will not be covered. Does this help?
EM says
We Love the Homely Sweetness of it
Isabella says
It's the best recipe I've ever found! I've made it too many times to count!
Paula Montenegro says
Thanks for letting me know Isabella!
Debra says
Can I use a 9x13 pan do I need to double the recipe
Paula Montenegro says
Hi Debra! The pan used is 13x18 inches, so you have to HALVE the recipe to make it in a 9x13 pan.
Debra says
Can I use a 9x13 pan
Paula Montenegro says
Hi Debra, you have to use two 9x13 pans for the whole recipe. Or make half the recipe and use one.
Monica says
I halved the recipe to use a 9 x 13 pan. The batter doesn't come up very far at all. Is that correct? It just seems like there isn't going to be much cake.
Diane Marie says
Could you use this recipe to make cupcakes?
Paula Montenegro says
Hi Diane, it's a fudgy cake and a soft glaze so be careful when adding the glaze as it will be a bit of a mess. You might get some cake stuck in the paper liners.
Elizabeth says
I want to make this recipe but I do not have a sheet pan. Do you think I could make it in a 9" X 13" cake pan?
Paula Montenegro says
Hi Elizabeth, 9x13 inches is half the size of the pan I use, so I recommend you make half the recipe.
Donna says
Paula, yes this a vintage recipe! I am 74 years old. My mother made a ""brownie recipe" very similar to your Chocolate Condensed Milk Cake when our family lived on a farm in southern Iowa. At that time, we had fresh eggs, raw milk, heavy cream! (raw-meaning it was right from the cow, separated into milk and cream and refrigerated.)!! Yes, my mother also put coffee in the frosting! We knew this dessert as 'Chocolate Creams'. In the summertime my dad would make homemade vanilla ice cream!! What a treat on a Sunday afternoon! No farm work on that day until milking time in the evening!!
Paula Montenegro says
I love this Donna! I'm 54 and also had milk's cream (top foam) growing up, directly from the milking yard. Dairy was so different back then. I love that these were brownies and it's not hard to imagine as the cake can be very fudgy if removed from the oven at the right time. Have a great rest of the year Donna.