Preheat the oven to 400 F.
Grate the zucchini with a box grater.
Chop the sun-dried tomatoes.
Add both the zucchini and the sun-dried tomatoes to a large mixing bowl.
Add the eggs, onions, oregano, and olive oil to the mixing bowl and mix well.
Add the flour and baking powder to the mixture and mix, making sure to well incorporate the flour.
Add the feta to the mixture and mix.
Pour the mixture into a well-greased casserole dish and bake for 45 mins or until puffy and golden.