Pre-heat your gas or charcoal grill. We are looking for a medium-high heat. Place the zucchini on your grill and char the skins, rotating your zucchini every 10 minutes until charred on sides. Total time should be about 30 minutes.
Place zucchini on a plate and allow to cool enough for you to handle. Peel the skins off and discard. Place the zucchini flesh in a colander for 30 minutes to drain excess liquid.
Place zucchini in a bowl along with garlic, lemon juice, salt and pepper and mash and mix with a fork until incorporated.
Add half the parsley, Feta and mix again. Taste, adjust seasoning. Transfer to a serving dish.
Garnish with grated Kefalotyri and remaining chopped parsley and serve with warm pita or crusty bread.