Preheat oven to 400°F. Spray a muffin tin with nonstick cooking spray.
In a large bowl, sift together the flour, cornmeal, baking powder, salt, and sugar. Make a well in the center and add the oil, soy milk, soy yogurt, vanilla, and lemon zest. Mix until just combined. Don't overmix.
Fill each muffin cup about ¾ full. Bake for 20 to 25 minutes, until a toothpick inserted in the center comes out clean.