Roast chicken and vegetable soup

Name: Roast chicken and vegetable soup
Prep time: 5 min
Cook time: 20 min
Total time: 25 min
Cuisine: British, European
Ingredients: 1 tbsp olive oil; 1 onion, finely chopped; 800 g leftover cooked roast carrots, parsnips and potatoes, roughly chopped; 2 cloves garlic, finely chopped; 7.5 g fresh thyme leaves, washed and picked; 1 litre chicken stock, made with 1 chicken stock cube; 300 g leftover roast chicken, shredded; Juice of 1 lemon; 4 tbsp half fat crème fraîche, to serve; 0.5 white baguette, torn to, serve