Preheat your oven to 375F and line an 8-inch round, nonstick cake pan with parchment.
In a large mixing bowl, whisk together the flour, sugar, baking powder, cinnamon, turmeric, salt, and pepper.
In another mixing bowl, combine the non-dairy milk and lemon. Allow it to sit for a minute, then stir in the oil and vanilla. Add this wet mixture to the dry ingredients. Whisk the batter together until only very small clumps remain.
Pour the batter into your prepared cake pan. Bake for 40-45 minutes, or until the center has set and the edges are golden. Allow the cake to cool completely before frosting.
While the cake bakes, make the frosting. Pour any excess liquid out of the coconut cream cans. Transfer the solid, cooled cream to a stand mixer fitted with a whisk attachment (alternately, you can use a handheld beater for this). Add the vanilla, salt and sugar. Beat for a few minutes on high speed, or until the frosting is light (it'll be more liquidy than regular buttercream, but thicker than a confectioners' sugar glaze made with water).
When the cake is cool, cover it with frosting. Garnish with coconut flakes, slice, and serve.