100-Hour Fudgy Matcha Brownies

5 from 7 votes

These Matcha Brownies are inspired by Alvin Zhou's 100-Hour Fudgy Brownies. They're so indulgent with melt-in-your-mouth white chocolate!

Prep Time1 40

Cook Time33

Rest Time4

Total Time4 1 13

Course: Dessert

Cuisine: Asian

Servings: bars

Calories: 576kcal

225 g / 2 sticks unsalted butter
4 eggs
1 tbsp vanilla paste
2 tbsp white drinking chocolate powder (one for the brown butter and one to sift into the batter)
30 g / 1 oz white chocolate powder ice cubes (16.5 g/0.6 oz sachet mixed with 200mL/0.8 US cup hot water; roughly 2 ice cubes made the night before)
45 g / 8 oz matcha powder
215 g / 1 1/2 US cup all-purpose flour
400 g / 2 US cup sugar (or to taste)
1 tbsp salt (use kosher if available)
100 g / 3 1/2 oz white chocolate
225 g / 8 oz matcha chocolate (to be melted)
125 g / 4 oz matcha chococlate (to be used as a topping)

Melt the unsalted butter on a low heat for 5 minutes or until it becomes brown butter and turn off the heat.
Add the white chocolate powder and stir until dissolved.
Put the ice cubes into the mixture and stir until melted, then set aside for later.
In a large bowl, whisk together the eggs, vanilla paste and sugar until it becomes fluffy.
Sift in the matcha powder, white chocolate powder and salt into the egg mixture, then fold in until well incorporated.
Pour in the brown butter and mix well.
Melt 225 g (8 oz) of the green tea chocolate in a heatproof bowl over a pot of simmering water on low heat, then add the melted chocolate into the batter and stir to combine.
Sift in the flour and fold in until mixed.
Roughly chop the remaining green tea chocolate bars and stir into the batter.
Line a 23 x 33 cm (9 x 13”) with baking paper, then smooth the batter out until it covers the entire tray.
Roughly chop all the white chocolate, then top it over the uncooked batter.
Cover the uncooked brownies with glad wrap and refrigerate for 3 days.

Preheat the oven to 180°C (350°F). Take the batter out of the fridge and bake for 30 minutes.
Note: Keep it on the middle or bottom oven rack because the white chocolate can burn easily.
Tightly cover the tray with foil and put the cooked batter into the freezer while it’s still hot for 30 minutes, then transfer it to the fridge for another 24 hours.

Preheat the oven to 180°C (350°F). Remove the tray from the fridge and take the brownie out.
Trim the edges away to make it neat and even.
Tip: Dip the knife in hot water with each cut to make it a cleaner slice. Also, if you have trouble taking the brownie out, run a small knife along the edges to loosen it from the baking tray.
Divide the brownie into 9 pieces, or to preference.
Heat the Matcha Brownies up for 3 minutes or until warm. Serve immediately as is!

Matcha powder. Different brands and types will produce different flavors and bitterness levels, so adjust accordingly.
White chocolate powder. I substituted espresso powder for white hot chocolate powder because I felt that would work better with green tea.
Matcha chocolate. I could only find Meiji Matcha Chocolate at my local Asian supermarket, but if you have a favorite then you can use that. Juts keep in mind the sugar levels would be different so will need to be adjusted to taste.
Sugar. Alvin uses 450g (1 1/2 US cup) sugar, but I found that by opting to just use white and green tea milk chocolate instead of including dark chocolate, there wasn't enough bitterness to balance the sweetness. So this Matcha Brownie recipe uses slightly less sugar.
White chocolate powder ice cubes. Make these the day before so you have them ready when you need them.
Keep the tray away from the grill. White chocolate burns at a much lower temperature. Make sure to use the middle or bottom rack if you want to keep the chocolate looking white.
Use a good quality matcha powder. We used Nature's Way Matcha Green Tea Powder because that's what we could find locally, but if you have a favorite that you love, go ahead and use that instead.
Avoid overmixing. Mix until you have just formed a dough, otherwise you run the risk of adding too much air into the Matcha Brownies.