Though Oiistar in Wicker Park has a very delicious standard tonkotsu bowl, some of the best ramen variations at this busy spot are the ones that break tradition. Oiistar successfully cross-pollinates ramen with other dishes and cuisines—from the Tikkamen which is flavored with masala, to the Pozolemen which is flavored with chipotle chiles. When combined with the pleasant chew of their thin, housemade noodles, it’s worth rushing to grab a bar seat after work before this place fills up for dinner.