Cut the chicken breasts in half. Whisk the olive oil and wholegrain mustard together in a bowl and add the chicken breasts. Toss to coat in the mixture and set aside for 20 minutes Heat a griddle pan until hot, then lay the pieces of chicken on it and cook for 4-5 minutes each side, until charred and cooked through. Remove from the griddle pan and set aside. Preheat the grill. Rub the French bread on both sides with the cut side of the garlic clove. Place on a baking tray and drizzle with the oil. Toast the French bread on both sides until golden, then spread one side with the Saclà Olive & Tomato Stir Through. Arrange the chicken on four serving plates with the rocket leaves. Top the crostini with the dolcelatte and add to the plates with the chicken and salad and serve straight away. Dolcelatte is a creamy blue cheese with a mild flavour. You can use Gorgonzola instead if you like, or if you prefer a stronger flavour, use Stilton.