Kolokithokeftedes (Greek Zucchini and Feta Fritters)

Name: Kolokithokeftedes (Greek Zucchini and Feta Fritters)
Cuisine: Greek, Mediterranean
Ingredients: 1 pound fresh zucchini; salt; 2 large eggs, beaten; 1/2 cup diced red onion; 3 medium garlic cloves, minced; 3 ounces feta cheese, crumbled; 1 cup all-purpose flour; 1 tsp baking powder; 1 tsp dried dill; 1 tsp dried oregano; 1 tsp dried thyme; 1/4 tsp freshly ground black pepper; 1/4 cup olive oil plus extra; tzatziki, Greek yogurt, and/or lemon wedges for serving