Steps

1. Thinly slice half an onion. (Secret Tip: Making a few horizontal cuts before slicing helps achieve uniform thickness.)
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2. Season 150g of thinly sliced beef with a pinch of salt and pepper to taste.
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3. Add 1 tbsp of all-purpose flour and mix well, ensuring it coats the beef evenly.
   🕒 01:16
4. In a bowl, combine 50g of mascarpone cheese, 1/2 tbsp of consommé granules, and 250cc of milk. Gradually add the milk while mixing to prevent lumps.
   🕒 01:31
5. Heat oil in a pan over medium heat. Add the spread-out beef and sear without moving until browned on one side.
   🕒 02:17
6. Flip the beef and sear the other side until browned. Remove from the pan.
   🕒 02:30
7. Add the onion to the same pan and sauté over medium heat.
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8. Add a pinch of salt to the onion and sauté until softened.
   🕒 02:52
9. Reduce heat to low. Add 1 tbsp of whole grain mustard and 150cc of white wine.
   🕒 03:00
10. Increase heat to medium and simmer until the liquid has evaporated and the flavors have concentrated. (Secret Tip: This step adds acidity and richness, significantly enhancing the taste.)
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11. Turn off the heat. Add the seared beef and the prepared sauce mixture.
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12. Turn heat back to medium and simmer for about 5 minutes until the sauce thickens and is ready to serve. (Secret Tip: Simmering concentrates the sauce, resulting in a rich umami flavor.)
    🕒 03:50