My list of favourite street food in Delhi would be:
1. Chache di Hatti, Kamla Nagar
2. Moolchand Parantha
3. Sita Ram Diwan Chand, Paharganj
4. Fateh Chand ki Kachori
5. Atul Chaat Corner, Rajouri Garden
6. Old Famous Jalebi wale, Chandni Chowk
7. Jain Chawal, Connaught Place