Rinse chicken fillets cold, dab dry and cut in half. Season with salt and pepper. Fry in hot oil while turning for about 15 minutes. In the meantime peel onions and cut them into sticks. Pluck rosemary needles from the stems.
Cut ham into cubes. Heat butter and fry onion. Add rosemary, ham and peas and steam for about 5 minutes. Season with salt and pepper. Remove the chicken fillets from the pan and keep warm. Add cream and lemon juice to the cooking fat and simmer for 3-4 minutes. Season with salt and pepper. Bind with sauce thickener if necessary. Arrange the chicken fillets on the peas.
Remove the chicken fillets from the pan and keep warm. Add cream and lemon juice to the cooking fat and simmer for 3-4 minutes. Season with salt and pepper. Bind with sauce thickener if necessary. Arrange the chicken fillets on the peas. Pour sauce over them