Small handful of fresh thyme (leave some to garnish)
2 tablespoons sumac plus extra to coat the chicken
3 chicken breasts, on the bone
Salt and pepper
Fresh pomegranate seeds
1/2 cup toasted pine nuts
In a bowl put the flour, black pepper, salt and sugar and mix. Put in the cold butter cubes and using your fingers rub the butter into the flour to make a crumbly consistency. Make a well in the center and pout in the water and egg. Bring the flour gradually together and mix quickly to make smooth dough. Flatten slightly into a disk and cover with plastic wrap. Refrigerate for one hour until ready to use.
Preheat the oven to 375 degrees F. Roll out the pastry to fit two 13-x4-inch tart pans with a removable bottom. Prick the base with a fork. Chill in the fridge for 20 minutes. Line the pastry with parchment paper (or foil); fill with dried beans to prevent it from rising and blind bake for 15 minutes. Remove the beans and paper; turn down the oven temperature to 350 degrees F and bake for an additional 15 minutes until they have a light golden color. Cool the pastry completely. Remove from the pan, place on flat serving platters and set aside.
Put the olive-oil in a large heavy-based pot. On medium heat sauté the onions and the garlic. Sprinkle in the salt, pepper and sugar. Stir to coat the onions well and turn down the heat to low. Add the fresh thyme. Cook gently, stirring, taking care not to burn them. The onions will caramelize and sweeten as they cook. This will take about 40 minutes. When they are melting softly, remove from the heat and stir in the sumac. They will turn a pinkish color. Pour into a colander sitting in a bowl to drain the excess oil.
Preheat the oven to 375 degrees F. Coat the chicken with olive oil, salt, pepper and sumac. Roast for about 30-40 minutes. When done, remove, cover lightly with foil and leave to rest.
To assemble the tart, spread the caramelized onions on the pastry. Remove the chicken from the bones, thinly slice and place on top of the onions. Garnish with pine nuts and a few fresh thyme sprigs and pomegranate seeds.