Medhu vadai or Ulundhu vadai(Tamil), Uddina vade (Kannada ಉದ್ದಿನ ವಡೆ), Malayalam: ഉഴുന്നു വട Uzhunnu vada, Tamil: ulundhu vadai), Medhu vadai, made with Urad dal (black gram) flour. This vadai is shaped like a doughnut, with a hole in the middle (i.e. an approximate torus). It is the most common vadai type throughout North and South India. -Source: Wikipedia