QUICK BRAISED RED CABBAGE SAUSAGES AND APPLES

2 tsp sunflower or vegetable oil • 8 Waitrose & Partners No.1 Lincolnshire Sausages • 2 Waitrose & Partners Jazz Apples • 2 tbsp red wine vinegar, plus 1 tsp • 1 large onion, thinly sliced • ½ red cabbage (about 450g), cored, quartered and shredded • 1 tbsp dark maple syrup (or 1 tbsp brown sugar and 1 tbsp water)