Cut smoked bacon into cubes and roast in a frying pan until crisp. Rinse herbs. Cut the chives into fine rolls, chop the parsley. Brush an ovenproof dish (at least 2 l capacity and 10 cm high) with a tiny bit of butter. Put bay spice on the bottom. Acidify the fish chops with the juice of one lemon and season lightly with salt. Remove peel from potatoes, rinse, drain and cut into thin slices. Put half of them in the form, season with salt and season with pepper. Add half of chive rolls and half of parsley on top. Spread half of the bacon cubes evenly on top. Place the prepared fish chops one after the other on the herb and bacon bed and layer the remaining bacon cubes, chopped parsley, chive rolls and potato slices one after the other. Season with salt and pepper.
Pour whipped cream on top and place remaining butter as flakes on top.
Cook in the heated oven at 225 °C (gas 4) for about 20 minutes with the lid closed (with a lid or with aluminum foil), then cook for another 50 minutes with the lid open so that the gratin gets a golden brown crust. If it browns too much, cover it again with aluminum foil.
Preparation time: 40 min Cooking time: 70 min
Joule (852 calories) Tip: In France, fish chops are always used for this gratin, i.e. fish with skin and bones, because the flavor is more intense.