Creamy Beef with Mushroom Sauce (Classic Recipe)

CLASSIC ROAST BEEF Ingredients: 1/2 kg beef (cut into pieces, pre-boiled) 1 small onion (chopped) 2 cloves garlic (chopped) 1/2 stick butter 1 can sliced mushrooms 2 tbsp soy sauce 1 box cooking cream (all-purpose cream) For the slurry (1 cup broth or water, 3 tbsp flour or 2 tbsp cornstarch) Salt and pepper to taste
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