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Alton Brown's Bake And Pause Method For Unbeatable Brownies

Instead of baking brownies at 325 degrees Fahrenheit for 25-30 minutes, Alton Brown uses a lower temperature and a brief pause in his "cocoa brownies: reloaded" recipe.

To make the center of his brownies extra gooey, he bakes them at 300 degrees Fahrenheit for 15 minutes and removes them from the oven to let them cool down for another 15 minutes.
Brown then resumes the process and bakes the brownies until they reach an internal temperature of about 195 degrees Fahrenheit, resulting in an impeccable texture.
The low temperature used in the initial baking phase prevents the delicate exterior of the brownies from crisping up too fast or getting burnt and keeps the interior undercooked.
Using a low temperature helps the brownies retain moisture and prevents them from drying out. Letting them rest helps the interior congeal and set slightly within the brownies.
The final baking phase, which requires the brownies to reach a core temperature of 195 degrees Fahrenheit, ensures the eggs and flour in the recipe are safe to consume.
Many might be tempted to skip the resting step and underbake the brownies in an attempt to get the desired texture, but consuming raw ingredients can lead to foodborne illnesses.
Similarly, baking the brownies continuously at 300 degrees Fahrenheit until they reach a safe temperature won't get the desired internal texture.
During baking, leavening agents make the batter rise and fluff up. Without a rest period, the batter will stay fluffy until it's baked through, resulting in a more airy texture.
Letting the batter settle down before you finish cooking disrupts that rising process and creates a more densely-compacted center that will remain gooey even when cooked.