Santouka Ramen, which has locations in Harvard Square (1 Bow St, Cambridge, MA 02138) and Back Bay (66 Hereford St., Boston, MA 02115), serves Hokkaido’s Asahikawa Tonkotsu Ramen. Currently, they have dine in, take out, and delivery options; UberEats (delivery and pickup), Grubhub (delivery and pickup), the Santouka website (pickup), and calling in (pickup).
I went with the Shio Tonkotsu ramen, but other options include Shoyu (醤油/soy sauce), Miso (味噌/fermented soybean paste), Karamiso (辛味噌/spicy fermented soybean paste), Gomamiso (ごま味噌/sesame fermented soybean paste), Neginanban (ネギ南蛮/spicy onions and jalapeno), and Vegetarian. The ramen comes with ネギ (green onions), メンマ (fermented bamboo shoots), 木耳 (kikurage) mushrooms, two pieces of チャーシュー (chashu/braised pork belly), an 梅干し (umeboshi/pickled plum), and ナルト(naruto/fish cake).
The broth is relatively thin and light, and savory. Though the division of cooked noodles from the soup in their takeout container creates some sticky noodles, it is overall a tasty ramen due to the great broth. Its proximity to the downtown area is also very nice, though there tends to be long lines to get in.