Place the duck breasts in a clay pot or an ovenproof dish with a lid.

Peel the garlic cloves but leave them whole.

Rinse the lemons and cut them in half.

Add the halved lemons, whole garlic cloves, bay leaves, and peppercorns to the duck breasts. 

Sprinkle with a generous layer of flaky salt.

Pour in oil until it covers the contents of the dish and put the lid on.

Place the dish in the oven.

Cook for 4 hours in the oven at 100 degrees Celsius (212 degrees Fahrenheit).

Remove the duck breasts from the oil.

Sear the duck breasts brown and crispy on the skin side in the oil that clings to them.