Preheat oven to 350 degrees Fahrenheit. Grease 2 9" pans and set aside.
In a large mixing bowl, whisk together dry ingredients ( cake flour, baking powder, salt, turmeric, and lemon zest). Set aside.
In another large mixing bowl, whisk together remaining ingredients (lemon juice, both sugars, vegan butter, oil, non-dairy milk, yogurt, and vanilla) until very well combined.
Slowly pour dry ingredients into wet ingredients. Use a spatula to fold together just until combined. DO NOT OVERMIX.
Pour into prepared pans evenly.
Bake for 30-40 mins or until a toothpick comes out clean.
Let cool before removing.
While cooling, into a large bowl, beat vegan butter and cream cheese together until creamy.
Add in powdered sugar 1 cup at a time, beating with mixer after each. Add in lemon juice, vanilla, and salt. Blend together again.
Spread or pipe frosting onto cake as desired.