1. Put grated zucchini into a colander, pour 1/2 tsp of kosher salt over top; let zucchini drain for 30 minutes. Pat dry with paper towels.
2. While the zucchini is draining, saute the finely chopped onion and garlic.
3. In a medium bowl, combine the zucchini, egg, onion, flour, bread crumbs, Parmesan cheese, salt, pepper and chili powder. Use hands and mix ingredients together.
4. Heat a small amount of oil in skillet over medium-high heat. Make small patties and drop zucchini mixture into pan. Cook for a few minutes on each side until golden.
5. Top each zucchini bite with a dab of sour cream.