For the dough, knead 200 g flour, salt, butter, 1 egg yolk and 3 tablespoons of cold water to make a dough. Wrap in foil and put in a cool place for about 30 minutes. Cut 4 slices of bacon into fine cubes. Heat the oil in a pot and let the bacon drain at medium heat. Add about 1 litre of water. Simmer lentils and bay leaf for 10-15 minutes.
Shortly before cooking, season the lentils with vinegar, salt and pepper and mace. Drain the lentils in a sieve and chill them. Put eggs, 1 egg yolk and milk in a bowl and mix. Season with salt, pepper and 1 pinch of sugar. Grease a flat ovenproof dish (26 cm Ø). Roll out the dough on a floured work surface to a circle (approx. 30 cm Ø). Place in the form, press the rim and prick the base several times with a fork. Clean, wash and cut the spring onions into rings. Cut the gorgonzola into large cubes. Mix the egg milk with the cold lentils, fold in the spring onions and gorgonzola and pour into the dish. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 60 minutes, remove from oven.
Roll out the dough on a floured work surface to a circle (approx. 30 cm Ø). Place in the form, press the rim and prick the base several times with a fork. Clean, wash and cut the spring onions into rings. Cut the gorgonzola into large cubes. Mix the egg milk with the cold lentils, fold in the spring onions and gorgonzola and pour into the dish. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for about 60 minutes, remove from oven. Fry 4 slices of bacon in a pan over medium heat until hot and place on the tart. Cut the tarte into pieces and serve
10 minutes waiting time