Fillet the oranges and collect the juice in a deep plate. Wash the lettuce and spin it very dry. Arrange on plates.
Wash the lamb fillet and pat dry. Cut into 2-3 cm thick slices. Salt, pepper and sauté on both sides for 2-3 minutes. Wrap in aluminum foil and let it steep in the oven at 120 ° C.
Pour 3 tablespoons of orange honey into the hot pan and bring to the boil. Deglaze with vinegar, red wine and 5 tablespoons of orange juice and reduce over high heat for 3-5 minutes. Season to taste with salt and pepper, add a little rosemary. Add orange fillets, reduce heat.
Spread the lamb fillets evenly on plates and pour the sauce over them.