Preheat oven to 180°C fan forced (200°C conventional).
Season the chicken thighs with salt and pepper.
Bring a large shallow cast iron casserole pan to a medium heat. Add the olive oil and then the chicken thighs, skin down. Leave to fry undisturbed for about 6 minutes, until golden and crispy. Turnover and brown on the other side. Once completely browned, remove the chicken from the pan and add another drizzle of olive oil if needed.
Add the bacon to the pan and fry until the bacon begins to brown. Add the leek to the pan and sauté until tender. Add the sliced garlic and sauté until fragrant.
Pour the white wine into the pan and use a timber spatula to lift any browned bits from the bottom. Add the chicken stock and mustard into the pan and stir to combine. Taste the liquid and add more salt to taste.
Next, add the potatoes and then the chicken, skin side up, back into the pan. Nestle the chicken into the vegetables so that it is mostly submerged in the liquid, with the crispy skin above the liquid. Add the thyme sprigs to the pan and then place into the oven on the middle shelf, to cook for 30 minutes.
After 30 minutes, add the asparagus into the pan and cook for a further 10 minutes.
To serve, spoon pieces of potato and asparagus onto each plate along with the leek and bacon. Top with a chicken piece and then spoon the liquid over the chicken and potatoes.
Notes
Nutrition facts are an estimate only - calories will be reduced drastically by removing the excess oil after frying the chicken thighs.