This is a building on recipes project, but a more simple one this time. You can prepare the buttercream while the cakes are baking and the ganache too.
Grease & parchment line 3-7" cake pans and preheat the oven to 350°F
For the Cake:
Combine ground flax seed with the 9Tbs of hot water and whisk smooth
Let stand for at least 5 minutes or up to 30 minutes to thicken to a paste
Combine the flour, sugar, salt, baking powder & soda together in a large mixing bowl
Combine the coconut oil, 1½ cup boiling water and cocoa powder together and whisk smooth
Add the cocoa mixture and the flax eggs mixture along with the vanilla extract to the flour mixture and whisk smooth
Pour batter into 3 greased and parchment lined 7" cake pans and bake immediately in a preheated 350°F oven for approximately 25-30 minutes or until the layers are springy to the touch when you gently press the centers
Cool cakes in the pan then flip them out onto a cooling rack to cool completely while you prepare the buttercream recipe of your choice
Add the mint extract and the green food color (*if using) adjust the extract to your taste, so start with just 2 teaspoons and add more as desired
Prepare the ganache and then decorate as shown in the video tutorial
Notes
Chocolate mint cake can be left at room temperature for up to 3 days in a cool environment, if it is too warm the cake may droop, but it won't go bad.
For longer storage keep refrigerated wrapped to prevent drying for up to 1 week.
Recipe by Gretchen's Vegan Bakery at https://www.gretchensveganbakery.com/chocolate-mint-cake/