Fillet Stroganov

Preparation:

Preparation: Cut the fillet into strips, flour it and brown it in plenty of butter over high heat. Drain it from the sauce and keep it warm. In the same pan, cook the chopped onion and shallots and 3 tablespoons of the tomato sauce. Add the mustard dissolved in a little broth and reduce. Season with salt and pepper and add 1 glass of 'sour' cream with a few drops of lemon juice, put the meat back in the pan, mix and let it rest for a while before serving.