Classic Creamy Beef Stroganoff with Mushrooms

Peel the onion and slice it thinly. Rinse the mushrooms briefly under cold water, pat dry, drizzle lightly with lemon juice to prevent browning, and slice evenly.

Heat 2 tablespoons of olive oil in a large pan over medium heat. Add the onion and mushrooms and sauté until lightly softened and fragrant.

Reduce the heat, cover the pan, and let the mixture simmer gently for about 10 minutes so the mushrooms release their juices and deepen in flavor. Transfer to a plate.

Slice the beef fillet across the grain into 0.5 cm thick slices, then cut each slice into thin, even strips.

In the same pan (or a second pan), heat 2 tablespoons of olive oil over medium-high heat. Sear the beef strips quickly in batches, stirring constantly, just until lightly browned.

Return the mushroom and onion mixture to the pan with the beef. Season with salt and black pepper, then drizzle the mustard evenly over the meat.

Pour in the cream and stir gently to combine. Bring the sauce just to a gentle boil, allowing it to thicken slightly.

Remove from heat immediately to keep the beef tender. Serve hot, ideally with pasta, rice, or mashed potatoes.