Spiced Potato & Carrot Latkes

Place onion, potatoes and carrots in a cheesecloth-lined colander set over large bowl. Let stand 5 minutes, squeezing occasionally. Drain off and discard all liquid in the bowl except white starch paste that settles at bottom.
Add onion, potatoes, carrots, eggs, 1/4 cup parsley, matzo meal, butter, salt, za’atar, baking powder (if using), pepper and cumin to the bowl with reserved starch; stir to combine.
In a large, heavy, non-stick skillet, heat 2 tablespoons oil over medium heat. Using a tablespoon, spoon potato mixture into skillet, using about 3 tablespoons per latke. (Skillet should hold about 3 latkes at a time.) Flatten mixture slightly with a spatula. Cook latkes 4 minutes, then flip and cook another 4 minutes or until brown, crisp and cooked through.
Remove latkes from the skillet, then transfer them to a serving platter and keep warm in a 300° F oven until serving.
Cook remaining latkes in batches, using 2 tablespoons oil in the skillet for each batch. Serve latkes with yogurt and remaining 1/4 cup parsley.