Meatballs with white wine mushroom sauce

Name: Meatballs with white wine mushroom sauce
Prep time: 35 min
Cook time: 35 min
Total time: 35 min
Yield: 6 portions
Ingredients: 80 g stale white bread; ½ onion; 4 sprigs fresh flat-leaf parsley; 1 tsp mixed herbs, dried; 20 g olive oil; 500 g beef rump steak; 1 egg; 20 g milk; ½ tsp fine salt; ½ tsp freshly ground black pepper; 60 g Parmesan cheese; 60 g dry white wine; 1 tbsp cornstarch; 1 garlic clove; 1 shallot; 40 g butter; 200 g button mushrooms; 1 pinch fine salt; 1 pinch freshly ground black pepper; 200 g cream; 1 sprig fresh flat-leaf parsley