Spatchcock chicken with blackberries and grapes

1 whole free-range organic chicken

sea salt and freshly ground pepper

chopped rosemary or thyme leaves

extra virgin olive oil or butter

a few cloves of garlic

For the sauce:

100g seedless grapes

300g blackberries

1 tablespoon pomegranate molasses

2 cloves of garlic peeled and crushed

¼ teaspoon cayenne pepper

1 teaspoon chopped marjoram

1 tablespoon chopped coriander leaves and stalks

pinch of chopped dill

sea salt and freshly ground black pepper

extra sprigs of coriander and dill for garnish