Preheat the oven to 220C/425F/Gas 7.
Place half of the olive oil into a small roasting tin and place into the oven for five minutes to heat.
Place the boiled new potatoes into the roasting tin with the heated oil. Season, to taste, with salt and freshly ground black pepper and return to the oven to roast for 10-15 minutes, until golden brown.
Meanwhile, heat a heavy-based ovenproof frying pan. Add the remaining olive oil to the pan, then add the chicken breast. Season, to taste, with salt and freshly ground black pepper, and cook for 1-2 minutes on each side, until light golden-brown all over.
Add the cherry tomatoes and drizzle over the soy sauce and balsamic vinegar.
Add the garlic clove and transfer to the oven to roast for 10-15 minutes, or until the chicken is completely cooked through and the cherry tomatoes are beginning to burst.
To serve, place the balsamic tomato chicken onto a warmed plate with the roast potatoes alongside.