Step 1

Preheat oven to 325 degrees. Grease an 8×8-inch cake pan with butter or a baking oil spray (I use coconut oil), and then line with parchment paper, and then spray parchment paper. Set aside.

Step 2

In a large bowl, mix together flour, sugar, cocoa powder, baking soda, and salt.

Step 3

Add water, oil, vanilla, and vinegar. Stir by hand until incorporated and the mixture becomes smooth.

Step 4

Pour batter into the prepared pan, spreading it evenly in one layer with a spatula, and then sprinkle with chocolate chips, if desired.

Step 5

Bake until a toothpick inserted into the center of the cake comes out clean, about 28 minutes.

Step 6

Remove from the oven and let cool completely.

Step 7

Dust with confectioners’ sugar, if desired.

Step 8

Cut into squares and serve.