Preheat oven to 350 degrees F. Prepare 2 round baking pans or 1 large rectangle baking pan by greasing with oil and lining the bottom with parchment paper. Lightly oil the parchment paper. Set prepared pans aside until needed.
Combine flours, sugar, cocoa powder, baking soda and salt in a large mixing bowl.
Make a well in the middle of the dry ingredients. Add the hot water, oil, vinegar, coffee granules and vanilla. Stir together until mixed well.
Pour batter into the prepared pans, dividing equally if using 2 pans. Place in the oven and bake for 25 to 30 minutes or until a toothpick inserted in the center comes out clean.
Allow the cake to cool in the pan for 10 minutes before removing to wire racks to finish cooling.
Cool completely before icing with your choice of icing.
Excellent cake for pairing with my Salted Dark Chocolate Buttercream Icing (not vegan).