Sausage cassoulet

Name: Sausage cassoulet
Ingredients: 1 tbsp vegetable oil; 12 Toulouse-style sausages; 200g bacon lardons; 2 onions finely chopped; 2 celery sticks, finely chopped; 2 garlic cloves crushed; 1 tbsp smoked paprika; ½ bunch of thyme leaves picked and roughly chopped; 200ml white wine; 400g can chopped tomatoes; 200ml chicken or veg stock (fresh or 1/2 a stock cube crumbled in 200ml water); 400g can butter beans drained and rinsed; 400g can haricot beans drained and rinsed; 1 tbsp caster sugar; 1 tbsp red wine vinegar; crusty bread to serve (optional)