Preheat the oven at 350 F.Combine the flour, egg, essential oil, vegetable oil, sugar, yogurt and orange juice in a large bowl and mix together.
In a smaller bowl combine the salt, baking powder, and baking soda. Add the dry ingredients to the orange mixture and mix well.
Add in the white chocolate chips and stir.
Fill cupcake liners ¾ of the way full with the mixture and bake 20 - 25 minutes at 350 F or until a toothpick stuck in the muffins comes out clean.
While the cupcakes are baking make the orange royal icing by adding all of the ingredients together and mixing well.
Once the muffins have cooled, drizzle the orange royal icing over the muffins.