Preheat the oven to 140 degrees top-bottom heat.
Put the butter in a saucepan and clarify. Remove the skin from the garlic and grate finely. Pluck rosemary and thyme leaves from the stems and chop finely. Beat and mix the eggs. Clean the liver, put it in a hand mixer and grind finely, gradually adding the clarified lukewarm butter. Season with pepper, salt, garlic and herbs and add the beaten eggs. Spread an ovenproof casserole dish of 700 ml capacity with the bacon slices so that they protrude 3 cm on each side. Pour the mixture into the dish and close it with the overhanging bacon slices. Place the baking dish in a water bath and poach in the heated oven for 40-50 min. Remove from the heat and cool.
Remove the peel from the celery and apples, cut into even strips and place in a suitable bowl. Mix orange juice, sour cream, mayo and juice of one lemon, season with cayenne pepper, salt and sugar. Mix vegetable strips with dressing and let sit for about 20 minutes. Then season repeatedly.
Cut the cooled terrine with a kitchen knife into slices about 1.5 to 2 cm thick and place one on each plate. Add the apple and celery salad. Cut black walnuts into slices and place on the plates for garnish.
Our tip: Use a deliciously spicy bacon for a delicious touch!