Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9×13 inch baking pan.
In a medium bowl, combine the flour, sugar, baking powder, baking soda, and salt. In a separate large mixing bowl, beat the oil and eggs together until well combined. Stir in the orange juice, orange zest, and vanilla extract.
Slowly add the dry ingredients to the wet ingredients and mix until just combined.
Pour the batter into the prepared pan.
Bake for 30-35 minutes, or until a toothpick inserted into the center of the cake comes out clean.
Allow the cake to cool in the pan for 10 minutes before removing it from the pan and allowing it to cool completely on a wire rack.
