3tbsp (1.5 oz)lemon juice + 1 heaping tsp lemon zest, from one large lemon
Instructions
Preheat oven to 350°F (177°C). Line an 8 x 8 inch baking pan with parchment paper.
Add eggs to a stand mixer with wire whisk attachment. Beat at highest speed for 8 minutes or until eggs turn thick and pale yellow. When you lift the beater, the mixture that drips off should be able to stay on top of your egg batter for several seconds before sinking back in. See photo in post for reference. You can do this with a hand mixer but it may take more time. See notes for more details.
While your eggs are beating, melt your chocolate. You can do this over the stove using the double boiler method or do this in the microwave. If you are using a microwave, add chocolate to a large microwave-safe bowl and heat for 1 minute. Then stir with spatula. Heat again for 30 seconds. Stir again until chocolate is completely melted and smooth. If chocolate is not completely smooth and melted, you can heat for another 20-30 seconds and stir again. You do need to be careful to not heat the full time all at once because you can overcook or burn your chocolate.
Once eggs are finished, fold them into the chocolate in 3 batches. First add in 1/3 of the egg mixture. Use your spatula to gently fold in the egg mixture. Make sure to scoop the chocolate from the bottom of the bowl so that all the chocolate gets incorporated. It's okay if your chocolate starts to get a little chunky. Fold until no egg streaks remain. Repeat with second third of egg mixture and then final third of egg mixture. It's okay if you have some small chunks of chocolate in your batter. Finally, gently stir in the lemon juice and zest until just incorporated.
Pour batter into prepared pan. Bake for about 30-35 minutes or until surface is dark golden brown and toothpick inserted comes out clean. Let brownies cool completely to set. Wait until brownies are cooled and set before slicing into squares with a sharp knife. The bottom of the brownies may be very sticky so you may need to use a thin spatula to release the brownies from the parchment paper.
Notes
Do not add lemon juice until the end. If you add it early, it will cause your chocolate to seize up and you won't be able to fold in your egg mixture.
You want to use your egg mixture very soon after it is done, otherwise it will deflate and lose air. If you are beating with a hand mixer, I recommend doing it after your chocolate is melted, so that your egg mixture can be used right away. You may need a few more minutes of beating when using a hand mixer to reach the right consistency.
This batter also needs to be baked right away.
The brownies are thin. I don't recommend baking them in a smaller pan or doubling the recipe for thicker brownies. I tested making them thicker but it cause them to fall apart too much and it changed the texture.
The nutrition information provided are only estimates based on an online nutritional calculator. This is not a comprehensive list of all the nutrients in the recipe (i.e., does not include vitamins, cholesterol, etc). I am not a certified nutritionist. Please consult a nutritionist or doctor for accurate information and any dietary restrictions and concerns you may have.