Ingredients :

2 tablespoons cooking oil
1 large onion, chopped 
3 cloves garlic, minced 
1 tablespoon chopped fresh ginger 
1 1/2 pounds ground beef 
2 1/2 teaspoons ground coriander 
2 1/2 teaspoons ground cumin 
1/4 teaspoon fresh-ground black pepper 
1/2 teaspoon turmeric 
1/8 teaspoon cinnamon
1 1/2 teaspoons salt 
1 pound boiling potatoes, peeled and cut into 1/2-inch pieces 
1 cup plain yogurt 
3/4 cup whole milk
3/4 cup frozen petite peas 
1 1/2 teaspoons lemon juice
1/2 cup chopped cilantro 

Method:
 

1-In a large deep frying pan, heat the oil over moderate heat.
2- Add the onion and cook until starting to soften, about 3 minutes.
3- Stir in the garlic and ginger and cook 1 minute longer.
4- Add the beef and cook until no longer pink, about 3 minutes. Drain off any fat. 
5-Add the coriander, cumin, pepper, turmeric, cinnamon, and 1 teaspoon of the salt to the pan.
6- Cook, stirring, for 1 minute. Stir in the potatoes, yogurt, and milk. Bring just to a boil.
7- Cover the pan. Reduce the heat and simmer for 20 minutes.
8- Uncover the pan and simmer for 5 minutes longer. 
9-Stir in the peas and the remaining 1/2 teaspoon salt. 
10- Simmer until the peas are just done, about 2 minutes.
11- Stir in the lemon juice and the cilantro.