
Udon is a thick white noodle made from wheat flour.  There are so many varieties of udon dishes and Nabe-yaki Udon is a more popular one in winter because it's very hot (not spicy hot).  Nabe-yaki udon has various toppings that you can choose.  Mine has a prawn tempura, egg, shiitake mushroom, kamaboko (fish cake), bamboo shoot and green vegetables in real hot broth. 
Photo @ Jinroku Restaurant in Higashiyama