Dab meat dry and cut into cubes. Dust with flour and fry thoroughly all around in hot oil. Season with salt and pepper. Peel and chop the onion. Add to the meat and fry briefly.
Add the stock and wine little by little. Cover and let it stew for about 1 hour. Sort, clean and wash the spinach. Cut smaller if necessary. Wash the lemon thoroughly. Cut one half into slices, squeeze the other half.
Add the spinach and lemon slices to the ragout about 20 minutes before the end of the cooking time. Whisk together the egg yolk and lemon juice. Remove the pot from the heat. Mix the egg yolks with 1-2 tablespoons of hot sauce.
Then add to the ragout while stirring constantly and thicken. Do not let it boil any more. Season to taste with salt, pepper and nutmeg. Flatbread tastes good with it.