Brown Butter Sourdough S’mores Brownies (from box mix)

Sourdough S’mores Brownies

We have a good friend who is in veterinary school right now, and we just traveled to Cumberland Gap National Park to camp near her school and visit her. My favorite part of the whole trip was our nightly campfires with s’mores, sitting around the fire playing our ukuleles and banjos. When we came back home with tons of leftover s’mores supplies, I just had to do something with all of it. Lately, I haven’t felt like baking from scratch this season. So, I decided to try my hand at fancying up a packaged mix with sourdough starter and fun toppings. The result: delicious sourdough s’mores brownies.

Using Brown Butter in Brownies

I’m a massive fan of using brown butter in any chocolatey baked good. Brown butter adds a nice, complex, nutty flavor that pairs exceptionally well with sourdough starter and chocolate. Now, the thing to note here is that brownies usually call for oil that is liquid at room temperature (avocado, olive, etc). So when baking from a box mix, we cannot evenly substitute the oil for butter, or else the brownies will be too dry. For this recipe, we use a combo of brown butter and some oil. This combination accounts for the butter substitution and the addition of sourdough starter.

Toasting the S’mores Brownies Topping

Once the sourdough brownies are fully baked, remove them from the oven and set the oven to broil. I recommend adjusting your oven rack if necessary. You don’t want the brownies too close to the top heating element; the center of the oven is best.

Sprinkle your s’mores topping over the brownies and broil for only about two minutes maximum! You need to watch the brownies carefully while broiling so you don’t burn the marshmallows or the chocolate.

Sourdough Discard

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Brown Butter Sourdough S’mores Brownies (from box mix)

Too tired for baking from scratch right now? Make baking a little easier and use your sourdough starter discard in this s’mores brownies recipe, made with your favorite packaged brownie mix!

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• Prep: 20 minutes
• Cook: 35 minutes
• Total Time: 55 minutes

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Ingredients

• 1 package brownie mix (~14 ounce pack)
• ½ cup butter
• ¼ cup avocado oil (or any neutral oil)
• 1 large egg
• 1 cup sourdough starter discard
• 3 tablespoons water
• 2–3 cups crushed graham crackers
• 1 ½ cups miniature marshmallows* (see notes)
• 1 milk chocolate bar, coarsely chopped
• ¼ cup dark chocolate chips

Instructions

1. Brown the butter in a small saucepan until bubbly, and dark golden to light brown. Stir it continuously, careful not to burn it.  Remove from heat and allow the butter to cool to room temperature, but still liquid.
2. Gather the other ingredients and preheat the oven to 350 degrees F.
3. Grease a 8×8-inch baking dish with a little cold butter, or line it with parchment paper.
4. Crumble enough graham crackers to line the bottom of the pan in an even layer. Leave the rest for topping.
5. Stir together the brown butter, oil, egg, water, and sourdough starter in a medium bowl until well blended.
6. Add in the brownie mix and stir until combined.
7. Pour batter into the prepared pan.
8. Bake in the preheated oven for about 35 minutes.
9. While the brownies are baking, make the topping. Break graham crackers into small pieces and place into a bowl. Add marshmallows and chopped chocolate and toss to combine.
10. Once they’re fully baked, remove brownies from the oven, and turn the oven to broil. (adjust your oven rack if necessary, you don’t want the brownies too close to the top heating element; center of the oven is best.)
11. Sprinkle the topping ingredients over the brownies.
12. Return brownies with the toppings to the oven and broil for 2 minutes until the marshmallows are just toasted. Don’t broil too long or you will burn the chocolate!
13. Let cool for about 5 minutes, then slice into 12 squares and enjoy.

Notes

• This recipe should work with most packaged brownie mixes, but the package needs to be about 14 ounces. The package I used was Birch Benders Organic Ultimate Fudge Brownie Mix (13.4 ounces). 
• Vegan marshmallows are really great for baking (I use Dandies brand). Since they do not contain gelatin, they hold up well. Any marshmallow should work here, though, since they are just quickly toasted via broiling.

Kaitlynn Fenley Author, Educator, Food Microbiologist

Kaitlynn is a food microbiologist and fermentation expert teaching people how to ferment foods and drinks at home.

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