In a bowl mix together mustard and marmalade
In a skillet heat the olive oil on medium heat and cook the chicken for about 5 minutes per side.
Spread the mustard mixture over the chicken evenly and add the blueberries to the skillet
Cook for 10 minutes stirring occasionally
Transfer chicken onto a serving plate.
In the same skillet add the vinegar to the blueberry mixture along with the salt and pepper and cook for about 10 minutes, stirring occasionally
Serve the chicken with a topping of the blueberry sauce.