BBQ sausage rolls with balsamic onions

Name: BBQ sausage rolls with balsamic onions
Prep time: 10 min
Cook time: 20 min
Total time: 30 min
Cuisine: Australian
Ingredients: 36.40 gm olive oil; 6 Butcher thin beef sausages, sliced into 2 inch pieces; 2 medium brown onions, cut into slices; 40.00 ml balsamic vinegar; 2 cloves garlic, finely chopped; 2 capsicums (1 red, 1 green), cut into medium slices; 4 White Long Rolls; 8.85 gm Dijon mustard; 200g Tasty Shredded Cheddar Cheese