In a large bowl, combine chickpeas, cumin, cornstarch, 1/4 c tahini,
1/4 c parsley, onion, and 1/4 c yogurt. Mix to combine, then using a
large fork or potato masher, smash the mixture until it breaks down into
coarse paste with only a few whole chickpeas remaining.
Form the mixture into golf ball-sized rounds and gently press down to
create patties.
In a large skillet, heat the oil until it sizzles when you drop in a
bit of the chickpea mixture. Gently and carefully arrange the patties in
the skillet and cook 5-8 minutes per side, or until deep golden brown
and crispy.
While the patties fry, combine the remaining yogurt, tahini, and
parsley, then season with salt and pepper to taste.
Remove the falafel patties from the heat and place on paper towels to
remove excess oil.
To serve, arrange patties on a platter with a bowl of the tahini-yogurt
sauce for dipping. Garnish with herbs if you have an extra lying around,
and enjoy!