Beef Steak Donburi

Ingredients for Beef Steak Donburi
(serves 2)

2 cuts of 100g Steak – beef tenderloin or sirloin (3½ oz)
Salt
Pepper
80g Onion (2.8 oz)
50g Eringi Mushroom – King Oyster Mushroom (1¾ oz)
2 Lettuce Leaves

– Onion Ponzu Sauce –
2 tbsp Sake
3 tbsp Grated Onion
3 tbsp Ponzu – citrus-based sauce
½ tbsp Grated Garlic
½ tbsp Butter

– Quick Homemade Ponzu –
1½ tbsp Soy Sauce
1½ tbsp Any type of Sour Citrus Juice (ex. yuzu, lemon or lime)
1 tsp Mirin or substitute: a sprinkle of sugar
A sprinkle of Dashi Powder

300~400g Steamed Rice (10½~14 oz)
Watercress or Broccoli Sprouts
Wasabi to taste