Heat oil in a pot and add sausages and ¼ cup water. Braise the sausages till the water evaporates and the sausages are light brown on all sides. Remove on a plate and set aside.
In the same pot, add star anise and fennel seeds. Saute for a minute and add the onions. Cook the onions for 3-4 minutes and add tomatoes, tomato puree, chili powder, coriander powder, garam masala and salt. Cook this mixture for a few minutes so that the spices are cooked a bit.
Add potatoes, 1 cup water and sausages to the pot. Bring this to a boil and simmer and cook for 10-15 minutes till the potatoes are cooked through. Switch off the flame and top with chopped coriander.
Serve this One Pot Curried Sausages and Potatoes with steamed rice or chapatis.