100 Hour Brownies? Yes, brownies that take 4 days to make. I had been seeing this technique all over my Instagram feed. I needed to find out if the all the hype was worth it. Join me on my journey to see.
The original technique was first reported by Alice Medrich in her book, Seriously Bitter Sweet: The Ultimate Dessert Maker’s Guide to Chocolate. She said that refrigerating the brownie batter in the pan for several hours, or as long as two days before baking, causes significant transformations. This process improves the top gloss and crustiness. It also blends the flavours, making the brownies taste much richer. The texture becomes chewier too.
Then Alvin Zhou posted a video on YouTube with a recipe for 100 Hour Brownies that went viral. Most of the 100 hours is hands off. The brownie batter is essentially aged for 3 days in the fridge before baking. The science behind this technique is that the flour in the batter becomes hydrated during the resting process. This leads to a super fudgy brownie.
Here’s a video showing you the best way to line you baking pan, so the brownies don’t stick.
Keys to Success in Baking 100 Hour Brownies:
- As always, the quality of chocolate makes a huge difference. This recipe uses over a pound of chocolate, so use a dark bittersweet chocolate ranging from 55-70%. I tested this recipe with both Callebaut 55% and Valrhona 64%. Both were excellent.
- Do not over bake brownies. They should be slightly jiggly in the center when you remove them from the oven.
- As soon as they come out of the oven, cover top with foil and set in freezer for 30 minutes. This traps in the steam and helps with moisture retention.
- Practice patience. After the freeze, let brownies rest in fridge for another 24 hours to chill.
The recipe I tested was created by Gemma over at biggerbolderbaking.com. It is perfect in every way and well worth the 100 hour wait. The brownies have an almost candy bar-fudge like consistency. Super creamy and very rich. Chocolate lovers will be smitten.
Try it soon.
100 Hour Brownies
Ingredients
- 400 grams bittersweet chocolate coarsely chopped
- 200 grams unsalted butter
- 6 large eggs room temperature
- 340 grams dark brown sugar
- 1 teaspoon vanilla bean paste or vanilla extract
- 1/2 teaspoon Diamond Crystal Kosher salt or 1/4 teaspoon Morton's Kosher salt
- 140 grams all-purpose flour
- 85 grams bittersweet chocolate chopped into 1]4 inch pieces
Instructions
- Day 1: Spray the bottom and sides of an 8 inch square baking pan with Pam and then line with parchment paper. Watch my video to see the most efficient way to do this.
- Melt 400 grams of chocolate and butter. You can do this in a bowl set over a pot of simmering water, or in a glass bowl in the microwave. If microwaving, go for 1 minute on 50% power, stir and add additional time in 10 second increments, at 50% power, until melted.
- Let melted chocolate/butter mixture sit for about 5 minutes. Whisk in eggs, one at a time. Mix in brown sugar, vanilla and salt.
- Fold in flour. Mix just until no white streaks remain. Stir in 85 grams chopped chocolate. Pour into prepared baking pan. Cover pan with fopil and refrigerate for 72 hours (3 days). This gives the flour in the batter lots of time to hydrate and gives you FUDGY brownies.
- Three days later: Preheat oven to 350°F. Remove foil from brownies and bake for 40-45 minutes. The brownies should be just about set in the center. You still want a slight jiggle. If you have an instant read thermometer, you are looking for a reading of about 200°F in the center of the brownies.
- Remove brownies from oven, carefully cover with foil and put pan straight into the freezer for 30 minutes. This traps the moisture and increases fuginess.
- Remove from freezer and place in fridge for 24 hours.
- 4 days later: Remove from fridge and cut into 16 squares. Store in an airtight container in fridge for 3 days, or freezer for up to a month.
