Chocolate Cake:
vegetable-oil cooking spray
1 cup warm water
½ cup unsweetened natural cocoa powder
1½ cups all-purpose flour
1 cup granulated sugar
¾ tsp. baking soda
½ tsp. salt
½ cup sunflower oil
1 Tbs. pure vanilla extract
2 tsp. distilled white vinegar

Chocolate Glaze:
2 oz. dark non-dairy chocolate, finely chopped
½ cup confectioners sugar, sifted
2 Tbs. water

For the cake: Preheat oven to 375 degrees and coat an 8-inch round cake pan with spray.
Whisk water and cocoa in a small bowl until smooth; combine flour, sugar, baking soda, and salt in a large bowl, and make a well in center; add cocoa mixture, oil, and vanilla; whisk until smooth; whisk in vinegar and pour into pan.

Bake until a toothpick inserted into center comes out clean, about 30 to 35 minutes; let cool on a wire rack for 20 minutes.

Run a knife around edge of cake, invert it onto rack, and turn cake right side up. Let cool completely. Transfer cake to a serving plate or a cake stand.

For the glaze: Melt chocolate in a heat-proof bowl set over simmering water, stirring until smooth; let cool slightly.

Whisk together sugar & water until smooth; add melted chocolate in a slow, steady stream; whisk until thickened (about 1 min.); immediately pour glaze onto center of cooled cake.

Using a spatula, gently spread glaze over top and sides. Cake can be stored at room temperature for up to 2 days.