Dice the chicken into 2cm pieces. Finely slice the garlic, then halve and finely slice the leeks before popping them into a colander and giving them a good rinse. Peel and finely dice the carrots. Pick the leaves from the thyme stems.

Add a shot of oil to a pan set over a medium heat, then add the chicken. Brown on all sides before removing the chicken from the pan. Set aside. Add the bacon and fry until golden and crisp. Add the carrots, leeks, thyme and garlic, then fry for 5 mins until the leeks are soft.

Add the flour and cook for 2-3 mins. Pour in the stock and simmer away for a couple of minutes until thickened. Return the chicken to the pan, then mix through 5 tbsp of the crème fraîche. Taste the sauce and adjust the seasoning. Set aside while you prepare the mash.

Heat the oven to 200°C. Peel and cut the potatoes into quarters, put them into a large saucepan and cover with cold, salted water. Bring to the boil and cook for 10-15 mins until the potatoes are tender. Meanwhile, grate the cheddar. Drain the potatoes and steam-dry for a couple of minutes, before mashing until smooth.

Transfer the mashed potato back to the same saucepan and put over a low heat. Add the butter and melt through, then stir through 2 tbsp crème fraîche and your Dijon mustard. Mix until combined, then season generously with salt and pepper.

Now your filling and mash are ready, it’s time to assemble! All you need to do is fill a deep casserole dish with the filling and then scoop the mash on top using an ice-cream scoop – if you don’t have one, use a spoon and smooth-out instead. Scatter over the cheese, then transfer the pie to the oven and bake for 25-30 mins until golden.