Ganso Mentai Nikomi Tsukemen is a ramen shop near Ikebukuro Station that serves tsukemen with mentaiko. You dip cold noodles into a hot mentaiko sauce, and the noodles are chewy and springy. On entering, you choose your noodle amount, up to 300 grams, and at 6 p.m. on a weekday you can get in without waiting, while at 8 p.m. on Friday the wait is about 20 minutes. Raising the spice level makes the sauce taste saltier.