Sumita すみた

Rated highly on Tabelog, a popular review site for restaurants in Japan, Sumita has been famous for their hand-made udon. Known for having long queues which thankfully move rather fast, they have benches that stretch down the adjacent lane for you to sit while you wait. Their udon, be it chilled or warmed in dashi broth, remains chewy to the last bite. The tenpura has a mildly thin batter that is fairly crunchy, wrapped around fresh vegetables and prawns. They have curry udon on their menu too. Sumita is one of my family's favourites, and will always be.

Tokyo Kita ku Shimo 2-52-8
東京都北区志茂2-52-8
11am-2pm, 6pm-9:30pm.
Except Weekend: 11am-3pm.
Closed on Mon, and 1st and 3rd Sun of the month. 
http://udonsumita.com