In a mixing bowl, combine the zucchini, biscuit baking mix, Parmesan, Cheddar, eggs, vegetable oil, onion, garlic, parsley, salt and oregano. Spread the mixture into a greased 9x13 inch baking pan and bake for 25 to 30 minutes, until golden brown.
Allow the mixture to cool. Cut into small squares and serve warm or cold.