Combine the flour, baking soda, salt, sugar, and turmeric in a bowl. Stir to combine. Set aside.
In a separate bowl, combine the water, vinegar, orange zest, and vegetable oil. Stir to combine. Pour the water mixture into the flour mixture and stir to combine. Make sure all big lumps of flour are mixed. This might take 40 seconds to a minute at most.
Pour the cake batter into the prepared baking pan. Bake for 30–35 minutes, until a toothpick inserted into the center of the cake comes out clean. When it's ready, remove the cake from the oven and set aside to cool completely before frosting.
For the Creamy Orange Turmeric Frosting
Place the butter and vegan cream cheese in a bowl and use a mixer to blend until light and fluffy. Add the powdered sugar, orange extract, orange zest, and turmeric. Continue beating with the mixer until a nice, fluffy consistency is reached. If it's a little too soft, add a little more powdered sugar. If it's too thick, add a teaspoon of plant-based milk.
Once the cake has cooled and the icing is ready, slather a thick layer of frosting on the cake. Prepare the Orange Sugar Crystals by combing one-half cup of sugar with food coloring. Stir until well combined and sprinkle this over the top of the cake.
Notes
In the cake, you can substitute 1 teaspoon orange extract in place of fresh orange zest. If you don't have orange extract or oranges, you can use any of the following instead: 1 teaspoon vanilla extract, coconut extract, or lemon extract.Mix up the zest! Use 1 teaspoon of orange zest combined with another teaspoon of lime zest, lemon zest, or even grapefruit zest for added flavor.