Egg-Free Brownies

1 . Stage

Preheat the oven to 350 degrees F (175 degrees C). Grease a 9x13-inch pan.

2 . Stage

Combine water and 1/3 cup flour in a heavy saucepan over medium heat; cook, whisking constantly, until thick. Transfer mixture to a large mixing bowl and set aside to cool, 15 to 20 minutes.

3 . Stage

Melt butter in a small saucepan over medium heat. Mix in cocoa until smooth; remove from the heat and let cool, about 15 minutes.

4 . Stage

Combine remaining 2 cups flour, baking powder, and salt in a small bowl.

5 . Stage

Add sugar and vanilla to cooled flour-water mixture; mix with an electric mixer until well combined. Add cocoa mixture and mix until incorporated. Add dry flour mixture and stir until just blended; fold in walnuts. Spread evenly in the prepared pan.

6 . Stage

Bake in the preheated oven until a toothpick inserted into the center comes out clean, 20 to 25 minutes. Cool before cutting into 20 squares.