What is better than a brownie? Fudgy chocolate marshmallow brownies! These easy brownie bars have a gooey marshmallow layer with added coconut. Topped off with some milk chocolate, this is the dessert bar of dreams!
Ingredients for the Best Homemade Marshmallow Brownies
These brownie bars can be divided into essentially three layers:
1. Brownie Layer
So, without doubt, the most important layer to a layered brownie is the brownie base! These are dreamy, decadent and super moist chocolate brownies to start this bake.
You can divide the ingredients for these into two groups: wet ingredients and dry ingredients. Unlike many recipes, this will be a strict adherence to wet and dry - no need to cream the fat and sugar first.
- Flavorless oil - you can use canola oil, vegetable oil or sunflower oil. In the UK, I often use rapeseed, but in the US you may find grapeseed or other similar oils. As long as it isn't a strong flavour (such as a bold olive oil) it should do the trick!
- Eggs - these should be at room temperature for best results.
- Vanilla extract
- Flour - either all purpose or plain flour will work here.
- Cocoa powder - a good quality cocoa powder is key to a bold chocolatey brownie.
- Sugar - for these brownies, use a combination of superfine granulated sugar (or caster sugar) and powdered icing sugar (or confectioners sugar).
2. Marshmallow Layer
For the marshmallow layer, all you really need is a bag of marshmallows! I also call for a bit of sweetened shredded coconut too.
The added coconut works well with the marshmallow for flavour and texture when these become melty and soft.
3. Chocolate Top
The chocolate top is two simple ingredients:
- Chocolate - I like to use milk chocolate here, but you could also use semi-sweet or dark, whichever you have available of have as a flavour preference. This needs to be in chip form or cut into chunks for melting.
- Butter - to add a glossy finish and a sheen to the topping, add a few tablespoons of butter once the chocolate is melted.
How to Make Marshmallow Brownies
The first step for these brownies is to line the baking tray with parchment. Trust me, with gooey marshmallows, you'll regret not putting a bit of parchment in the pan when it comes to getting them out!
I always use an 8" square tin for my brownies, blondies and bars.
Fudgy Brownie Layer
In order to make the brownie batter, this is a simple process of whisking the wet ingredients in one bowl and the dry in another. Then add the dry on top of the wet and stir to incorporate. Don't whisk or beat - there's no need - a spatula will do the trick.
Once you have your batter, pour this into the pan and spread into the sides and corners. This is a very thick batter, so the spreading will be key to ensure the whole tray is covered in a layer of brownie.
Adding Marshmallows to Brownies
Marshmallows go through an interesting process when they're heated. At first, they'll puff up and expand, before they break down and become liquidy.
The key to adding marshmallows to brownies (and still having a gooey marshmallow layer) is to add them near the end of baking.
For this recipe, once your brownies are done (after about 30 minutes of baking), take the tray out of the oven and sprinkle with a mix of the marshmallows and shredded coconut. This is why mini marshmallows are easiest to work with - they'll provide best coverage. And you're aiming to cover the top of the brownies in a layer of the mini marshmallows.
Place this back in the oven for about 3 minutes, until the marshmallows are swollen. Any less time and they won't have melted together at all, any more time and they'll start to toast and eventually break down.
Adding Chocolate to the Top
To make these marshmallow brownies with a chocolate topping all you really need to do is melt down the chocolate. Plus adding a few tablespoons of butter will add a glossy shine.
Melting chocolate should always be done in a double boiler style set up - in a bowl fitted over a saucepan of simmering water. It is important not to directly heat chocolate or to get any water in the chocolate as this will cause it to seize.
After melting, add the butter and stir until it dissolves into the chocolate, forming a thick glossy mix.
To top off the brownies, once your marshmallows are baked and slightly puffed up, you have two options:
- Drizzle chocolate - this is easier, but for a nice drizzle of the thick milk chocolate topping, you'll want to use a piping bag.
- Spread the chocolate - this must be done carefully and might take a little longer to gently coat the whole top of the marshmallow brownie bars.
How to Cut Marshmallow Brownies
Now that you've made your brownies, I'm sure you will want to dig right in! But here's my one piece of greatest advice when it comes to brownies (and also specifically chocolate marshmallow brownies) - waiting will be rewarded.
Fudgy brownies will not cut well or cleanly until they've had a chance to cool thoroughly. For the brownie layer alone, I would say leave these at least an hour before slicing. But with the marshmallow and chocolate topping, you will want to leave it even longer.
For the cleanest cut through these chocolate marshmallow brownies, you want to wait for the chocolate topping to have set. The timing here will vary a bit dependent on the warmth and humidity of your kitchen. Leaving for about 4 hours is best, but if you can't wait (which I couldn't when I was taking these pictures), 2 hours is plenty for getting a reasonable slice.
When cutting through anything involving marshmallow, aim to cut straight down and not to drag the blade. This will help the slices to cut more easily. Wipe your knife regularly with warm water to keep it clean of any stickiness or excess.
These brownies with marshmallow and chocolate keep well for several days. They a fantastic make ahead dessert and stay fresh for about a week at room temperature.
I wouldn't recommend refrigerating these brownies. The refrigerator won't increase the shelf life of the brownies and may in fact stale them more quickly once sliced.
Absolutely! I'm a coconut lover, so like to add it whenever possible. If you or someone who you'll be serving these to is less a fan, you can make these brownies in the same way simply leaving out the shredded coconut. This won't impact the baking, chocolate topping, slicing or storing at all!
If you like these brownies, try out some other brownie and blondie bars:
Chocolate Marshmallow Brownie with Coconut
- 8" square baking tray
- large mixing bowl
- 2 eggs
- ½ cup flavourless oil such as canola oil or sunflower oil
- 2 tablespoon water cool tap water
- 1 teaspoon vanilla extract
- 1 cup superfine granulated sugar or caster sugar
- ⅔ cup all purpose flour or plain flour
- ⅔ cup cocoa powder
- ½ cup powdered sugar or icing sugar
- ½ teaspoon salt
- 5 oz mini marshmallows half a standard sized bag or use full size marshmallows cut in quarters
- 2 oz sweetened shredded coconut flakes or substitute with dessicated coconut
Ingredients for Milk Chocolate Topping
- 5 oz milk chocolate chips or solid chocolate cut into chunks
- 3 tablespoon unsalted butter room temperature
- Begin by preheating your oven to 350°F (175C/155C Fan) and lining an 8" square baking tray with parchment paper.
- In a large mixing bowl, whisk together the wet ingredients - the eggs, oil, water and vanilla.
- In a separate bowl, stir together all dry ingredients - the sugar, powdered sugar, flour, cocoa powder and salt. Add this to the bowl of wet ingredients and stir with a spatula to combine into a thick brownie batter. Try to avoid over mixing but ensure no lumps of unmixed dry ingredients are left.
- Pour this batter into the prepared baking tin and gently smooth into an even layer, nudging the mixture into the edges and corners with a spatula.
- Bake in the centre of the pre-heated oven for about 30 minutes. For fudgey chocolate brownies, check for a toothpick inserted in the centre to come out with a few bits on it.
- Remove from the oven temporarily in order to sprinkle with coconut and mini marshmallows then place back in the oven for about 3 minutes until the marshmallows begin to look a bit swollen.
- Remove the brownies from the oven again and allow to cool in the tray while to prepare the chocolate topping.
- Bring a small amount of water to a simmer in a saucepan and turn down to a low heat. Meanwhile, place the chocolate in a small bowl, that will sit snuggly over the saucepan (like a DIY double boiler).
- Gently melt the chocolate in this DIY double boiler. Then remove from the heat and add the butter, stirring until melted into a glossy thick chocolate spread.
- Drizzle or spread this over the marshmallows and allow to cool for at least two hours before removing from the pan and slicing. (see note)