Homemade Buttermilk Brownies

Step 1 -Preheat the oven to 375 degrees F.

Step 2 -Line a 10x15-inch jelly roll pan with aluminum foil and coat it lightly with nonstick spray.

Step 3 -In a large mixing bowl, add the flour, the baking soda, and the salt and whisk to combine.

Step 4 -In a saucepan, add 1 cup of the butter, 1/2 cup of the cocoa powder, the granulated sugar, the light brown sugar, and the water and stir to combine.

Step 5 -Bring the cocoa mixture to a boil over medium heat and then immediately transfer the saucepan from the heat.

Step 6 -In a small bowl, add 1/2 cup of the buttermilk, the eggs, and 2 teaspoons of the vanilla and whisk them lightly together with a fork to combine.

Step 7 -While constantly whisking, slowly add the buttermilk mixture to the warm cocoa mixture until fully combined.

Step 8 -Pour the chocolate mixture into the dry ingredients mixture and mix until smooth.

Step 9 -Pour the batter into the prepared pan.

Step 10 -Bake until the center of the brownies is set, about 20 minutes.

Step 11 -In a saucepan, add the remaining butter, the remaining cocoa powder, and the remaining buttermilk and stir to combine.

Step 12 -Cook the buttermilk mixture over medium heat until just boiling, then immediately transfer the saucepan from the heat.

Step 13 -Add the powdered sugar and the remaining vanilla to the buttermilk mixture and whisk to combine.

Step 14 -Immediately spread the frosting over the still-warm brownies.

Step 15 -Top the brownies with the sprinkles, then slice, and serve.