Drain and rinse the chickpeas, then pat them thoroughly dry with a paper towel to ensure the falafel achieves a crispy exterior.
Place the chickpeas, egg whites, hemp hearts, parsley, cilantro, garlic, cumin, coriander, salt, and pepper into a food processor.
Pulse the mixture several times until it is well combined but still retains a slightly coarse, pebbly texture; do not blend into a smooth paste.
Form the mixture into four thick patties or six smaller rounds, pressing firmly so they hold their shape.
Heat the extra virgin olive oil in a large non-stick skillet over medium-high heat.
Carefully place the patties in the skillet and sear for 3 to 4 minutes per side until they are deeply golden brown and firm to the touch.
While the falafel is cooking, whisk together the Greek yogurt, tahini, and lemon juice in a small bowl until the sauce is creamy and smooth.
Serve the hot falafel immediately, drizzled generously with the zesty tahini sauce.