I don't eat tsukemen all that often but this one was incredibly delicious. So much so I went back twice. Situated in the shotengai in Takadanobaba not to far from the station. Easy to get to and you order from a ticket machine, so it couldn't be easier. 

The broth is seriously next level and the egg is something crafted from the heavens. Unfortunately they do not do noodle refills, but you'll be pretty full with the medium and up size. 

Some side donburi options if that's your thing but I've only ever eaten the Tsukemen. Highly recommend the Ajitama Tsukemen 味玉つけ麺. There's extra katsuoboshi and onion to add to your hearts content.

There also a bowl I got on my 2nd visit that's completely covered in chashu! 

つけ麺ひまわり (Tsukemen Himawari)