Do you love this dressing? Chances are if the salad dressing is good, the rest of the food in the restaurant is good. Bill and I both love this dressing and I've been trying to make it for years. I did an internet search and came up with the following which is adjusted to our taste:

Combine in blender:
1/2 cup mild oil (I used Peanut Oil - Canola didn't taste good) + a few drops of Asian sesame oil
1/3 cup Kikkoman Lite Soy Sauce
1/3 cup diced onion
1/3 cup diced celery (both the onion and celery are going into the blender so they don't have to be diced very finely)
3 tbsp + 1 tsp rice vinegar
2 tbsp diced fresh ginger (prepare same as onion and celery...I use a mini food processor)
1 tbsp sugar
1 1/2 tsp grated lemon peel (I use reconstituted dried peel from Penzey's)
ABOUT 2 tbsp ketchup (recipe only called for 1/2 tsp...but that was way too little)
1/4 tsp black pepper

Process on lowest setting. Don't completely pulverize the ingredients.
Store in a covered jar in the fridge. Shake thoroughly before using.