Place dried tangerine peel in a small bowl and add hot water to cover. Let soak for 15 to 20 minutes, or until the tangerine peel softens. Drain and finely slice. Transfer 2 tablespoons of sliced tangerine peel to a bowl. You can save the rest of the rehydrated tangerine peel in an airtight container in the fridge for next time or discard it. If you do not use dried tangerine peel, grate an orange to make 1 tablespoon orange zest, or thinly slice 2 tablespoons of tangerine peel (*Footnote 2).

Add the rest of the sauce ingredients to the bowl with the tangerine peel. Mix well.

Combine chicken, oil, and salt in a big bowl. Mix well and let marinate for 15 minutes.

When you’re ready to cook, add the beaten egg. Stir to mix well. Add cornstarch. Stir to coat chicken, until it forms an uneven coating with a little dry cornstarch left unattached.

Heat oil in a large skillet until hot, just starting to smoke. Add chicken all at once and spread into a single layer in the skillet. Separate chicken pieces with a pair of tongs or chopsticks.

Cook without touching the chicken for 2 to 3 minutes, or until the bottom turns golden. Flip to brown the other side, 2 to 3 minutes. Transfer chicken to a big plate and remove the pan from the stove. Let cool for 2 to 3 minutes (very important, so the chicken crisps up further).

Place the pan back on the stove and turn to medium heat. You should still have 1 to 2 tablespoons of oil in the pan. If there’s too much oil, pour out or use paper towels to remove the excess oil. Add green onion and garlic. Cook and stir a few times until it releases fragrance.

Stir the sauce again to dissolve the cornstarch completely. Pour into the pan. Stir and cook until it thickens.

Add back the chicken. Stir to coat chicken with sauce. Transfer to a plate and serve hot as a main dish.