Dashino-Moto だしの素
Dashino-Moto - fish bouillon, usually bonito
I don't like to advertise products of particular company, but dahino-moto is allround taste maker. It includes certainly chemical stuff, but not so harmful, I believe, I hope.... I am not sure. Anyway it is not expensive as you need only a litte for meals. For example, you can make sauce or soup for noodles with mixing little dashino-moto and soy sauce. It is much cheaper than the bottle of the sauce. Or you can add just a little for Miso-Soup.
Ajino-Moto - 味の素
Tonkatsu Sauce とんかつソース
In every country there are some best selling instant sauce. Heinz ketchup, Magie bouillon, etc. I suppose that the Japanese food maker or cook must have learned a lot from British worcester sauce. In Japan it is called Ustah-Sauce. Japanese people look like fond of thick sauce. They changed Indian curry sauce thick, British worcester sauce thick. There, the big hit "tonkatsu-sauce" was born. You can try Japanese worcester sauce, middle thick sauce or thick tonkatsu-sauce according to your favourite.
Shichimi 七味
Names are variated, shichimi, ichimi, or tohgarashi, but all taste more les same. It is powder made with red pepper. However it is a monopol market in Japan where only one or two major companies are producing. This red pepper powder is for many Japanese essential flavour for Udon, but somehow nobody sprinkle over Rahmen.
Furikake ふりかけ
Furikake - scatter, sprinkle over
I have no idea how it is made on the factory. This powder with various flavour is a long seller for more than 50 years. Many kids love it. Sprinkle over their favourte on the boiled whilte rice. You don't get it at the restaurant. Buy it at the Asian grocery.