• Prep the vegetables - dice the onion and thinly slice the mushrooms.
• Heat a large pot on medium high heat. Brown and the beef and season with ½ teaspoon of kosher salt. Drain the fat (optional), then add the butter and diced onions. Cook for 10 minutes on medium heat, or until the onions are soft. Taste an onion to make sure it’s not crunchy.
• Add the sliced mushrooms. Cook for another 3 minutes, then add the flour and garlic and cook for another minute.
• Deglaze pan with vinegar, then add the dijon mustard.
• Give everything a mix, then add the stock. Cook for another 5 minutes on medium heat, then turn off the heat and add the sour cream.
• Taste and adjust seasoning. Serve over egg noodles.

For the egg noodles

• Bring a pot of water up to a boil. Salt with 1/2 teaspoon of kosher salt. Cook the egg noodles according to package directions. Strain. This is ready to be mixed with the stroganoff, or served with the stroganoff on top.