Steps

1. Finely chop 1/2 onion. [This is the trick!] By leaving the stem end intact, cutting halfway from the top, you can finely chop it without it falling apart.
   🕒 01:38
2. Place the finely chopped onion into a plastic bag.
   🕒 03:00
3. Add 1/4 tsp salt to the onion in the plastic bag and knead until it softens. [This is the trick!] Kneading with salt softens the onion, allowing it to mix well with the ground meat without sautéing.
   🕒 03:05
4. Once the onion releases its moisture, add 1 tbsp potato starch and knead again. [This is the trick!] Potato starch traps the moisture and improves the mixability with the ground meat.
   🕒 03:39
5. Add 150g ground pork and 1 tbsp soy sauce to the plastic bag.
   🕒 04:05
6. Grate 1 potato with the skin on and add it directly to the bag. Grate and add 1 clove ginger as well.
   🕒 04:34
7. Knead everything well from the outside of the plastic bag to create the hamburg steak mixture.
   🕒 05:27
8. Divide the mixture into 2 portions, flatten them slightly while removing air, and shape them into oval patties.
   🕒 05:37
9. Heat a frying pan and add olive oil to taste.
   🕒 06:46
10. Place the shaped patties in the frying pan and sear them quickly over high heat.
    🕒 07:07
11. Once browned on one side, flip and lightly brown the other side.
    🕒 07:23
12. Flip and lightly brown the other side.
    🕒 07:23
13. Add 100ml tomato juice, and as soon as steam rises, cover with a lid and steam-fry over medium-low heat for about 5 minutes. [This is the trick!] Creating steam results in a fluffy and juicy finish, and it cooks through faster.
    🕒 07:33
14. After 5 minutes, remove the lid and transfer the hamburg steaks to a plate.
    🕒 08:04
15. In the remaining liquid in the frying pan, add 2 tbsp Worcestershire sauce and 2 tbsp ketchup, bring to a boil to make the sauce.
    🕒 09:03
16. Turn off the heat and stir in mustard to taste, if desired.
    🕒 09:48
17. Pour the sauce over the hamburg steaks on the plate, and it's done.
    🕒 10:08