Preheat oven to 350F. Spray baking spray on an 8” round cake pan and place pan on a parchment lined baking sheet. Set aside.

Bring the 1 ½ cups of water to a boil.

In a large bowl, sift together the sugar, all-purpose flour, cake flour, cocoa powder, baking soda, and salt until thoroughly combined.

Gradually whisk the boiling water into the dry ingredients, adding the water in small increments. The batter should be smooth and relatively thin.

Whisk in the eggs one a time, blending well after each addition, and then whisk in the oil. The batter will be very thin and oily.

Pour the batter into the prepared cake pan on the baking sheet; it will fill the pan almost to the top. Carefully place the cake pan/baking sheet in the oven and bake at 350F for 50-55 minutes, or until a toothpick inserted into the center of the cake comes out clean.

Remove cake from oven and let cool on a wire rack for 30 minutes, then invert onto a wire rack to continue cooling. Cool completely before adding glaze.

Whisk all ingredients together and pour over cake. Let set in the fridge for 15-20 minutes. Bring to room temperature before serving.