Tonkotsu vs. Shoyu Ramen.

These two words are not opposites, which is the source of most of the confusion. Tonkotsu describes the broth: pork bones boiled hard until the collagen and fat emulsify into something opaque and creamy. Shoyu describes the tare, the seasoning base, which in this case is soy sauce.

A bowl can be both. Tonkotsu shoyu ramen is a real and common thing. But on most menus the two are listed as alternatives, and when they are, "shoyu" means a clear chicken-or-pork broth seasoned with soy, and "tonkotsu" means the thick white one.

The two things every bowl of ramen has

Every bowl is built from a broth and a tare, and the menu names the bowl after whichever the shop wants you to notice.

• The broth is what the liquid is made of: pork bone (tonkotsu), chicken (tori paitan when boiled cloudy), seafood, kelp and dried fish (dashi), or a blend.
• The tare is the concentrated seasoning added to the bowl before the broth: soy sauce (shoyu), salt (shio), or fermented soybean paste (miso).

Once you know this, ramen menus stop being a list of unrelated names and become a grid.

Tonkotsu

From Fukuoka, on Kyushu. Pork bones — femur, trotter, sometimes head — are boiled at a rolling temperature for eight to eighteen hours. That violence is the technique: the marrow, collagen and fat break down and emulsify into the water, and the broth turns opaque white with a texture closer to thin cream than to soup.

It tastes deeply porky, slightly sweet, and coats the mouth. The classic Hakata-style bowl serves it with very thin, firm, straight noodles, chashu pork, a little green onion, and not much else — the broth is the dish.

At Hakata shops you can ask for noodle firmness. Barikata is very firm, katamen firm, futsu normal. Because the noodles are thin they soften fast, which is also why kaedama — a second helping of noodles dropped into your remaining broth — exists.

Shoyu

The older and more Tokyo-associated style. The broth underneath is usually chicken, or chicken with pork and a dashi of kombu and dried fish, simmered gently so it stays clear. Soy sauce tare gives it colour — brown and translucent — and a savoury, slightly sharp edge.

It is the more restrained bowl. You can taste the individual components: the chicken, the smoke of the dried fish, the salt-and-caramel of the soy. Noodles are usually thicker and often wavy, and the toppings tend to be more visible — menma, nori, a marinated egg, sometimes spinach.

Side by side

Which should you order?

Order tonkotsu if this is your first serious bowl of ramen. It is the most immediately impressive, and its appeal does not require you to notice anything subtle.

Order shoyu if you want to judge the shop. A clear broth hides nothing — every shortcut in the stock shows up in the bowl. It is also the better order when you plan to eat a full meal afterwards, or when you have had tonkotsu enough times that the richness has started to feel like a wall.

And if the shop is known for miso, order miso. Miso ramen is from Sapporo, uses fermented soybean paste as the tare, and is a third thing entirely rather than a variation on these two.

Where to eat it in the South Bay

Forkelo ranks the best tonkotsu ramen in the South Bay — scored on evidence about the bowl, not the restaurant's overall rating, which in ramen shops is dominated by wait times.

If you are still working out how to order, read the beginner's guide to ordering ramen, or browse every ramen ranking.