This was very easy.
I found inexpensive Australian beef package the other day. For 1 kilogram, it was 780 yen.
I made small beef wrap about 100 grams each and put into freezer and have been using it for cooking.
100 grams of beef. ( Thinly sliced. )
1 potato and Mentsuyu ( bottled sauce for noodle)
1. Cut the beef into bite size.
2. Peel the potato and cut into bite size.
3. Heat the pan and start cooking potato with oil till the potato turns brown. ( Salt and pepper)
4. Then take out the potato. In the same pan, start cooking the beef.
5. When the beef is cooked, add 2 spoonful mentsuyu. Cook 2, 3 minutes.
Prepare steamed rice in the bowl and put the above on it. Enjoy !