Just don't over cook the potato - if it's too soft it won't "survive" the second part of cooking (with onion and yogurt) and you'll end up with a big mush....
How to make it...
- 1 cup diced sweet potato (one medium large)
- 1 tablespoon clarified butter or rapeseed oil
- 1 cup diced onion
- 1 minced garlic clove
- 1/2 teaspoon coriander seed
- 1/2 teaspoon cumin
- 1/2 teaspoon cardamom
- 1 1/2 teaspoon garam masala
- 1/2 teaspoon grated fresh ginger
- 1 teaspoon salt
- 1 cup crushed tomatoes
- 1/3 cup Greek yogurt, full fat
Boil a pan of water, peel and dice (into 1 cm cubes) potato and boil it until just tender, but still with a little bit to it. If you're cut for time just microwave the sweet potato with 1/4 cup water for three minutes. Drain and set aside.
Heat the clarified butter in a saucepan. Add the onion and garlic and saute over medium heat until well caramelized. Add the coriander seed, cumin, cardamom, garam masala and ginger and toast in the butter and onions for a minute or two, until all is very aromatic.
Add the tomatoes, salt and sweet potatoes and bring to a boil. Turn down to a slow simmer, cover and cook for about 5 minutes. Remove the cover. Stir in the yogurt and cook for five more minutes or until piping hot. Serve warm as an accompaniment / side dish.