In a small bowl, whisk together the orange juice, milk, zest, vanilla, butter and sugar. Add in the flour, salt, baking powder and baking soda and whisk again to combine everything. Transfer batter to a mug or small ramekin dish.
Place in the microwave and cook for about 1- 1/2 minutes, until the cake has risen and is no longer jiggly.
Allow the cake to cool slightly and make the glaze in the meantime by whisking together the orange juice, powdered sugar, and salt in a small bowl. Drizzle the glaze over the cake and top with orange zest, if you’d like.