Preheat the oven to 200°C.
Coat the rabbit pieces thoroughly in flour and shake off any excess.
Season the rabbit with salt and pepper.
Fry the rabbit pieces in oil over medium heat for 5 minutes until golden.
Transfer rabbit to a baking sheet and roast in the oven for 6 minutes.
Fry sliced onions in the same pan for 5 minutes while scraping the bottom.
Deglaze with sherry, bring to a boil, and reduce volume by two thirds.
Add garlic, capers, and stock then simmer to reduce liquid by a third.
Return the rabbit to the pan with walnuts, olive oil, and lemon juice.
Adjust the seasoning with salt and pepper to taste.
Divide cooked linguine onto four plates and top with the rabbit mixture.
Garnish with fresh chopped parsley and serve.