Heat oil in a large frying pan or skillet over medium-high heat.
Add onions. Sauté, stirring occasionally, for about 2-3 minutes or until browned.
Add ginger, garlic, and green chilies (if using). Sauté, stirring, for 2 minutes or until fragrant.
Add ground turmeric, ground coriander, and red chili powder. Sauté, stirring, for about 40 seconds or until aromatic.
Add tomato paste. Sauté, stirring, for about 2 minutes.
Add ground (minced) meat. Season with salt and pepper.
Cook, breaking up with a wooden spoon, for about 10 minutes or until browned evenly.
Add potatoes.
Stir to combine.
Cook, stirring occasionally, for about 15 minutes or until potatoes are tender.
Add yogurt, garam masala, and chopped coriander (cilantro) leaves.
Cook, stirring occasionally, for about 3 minutes.
Garnish with coriander (cilantro) leaves.
Serve with naan or rice.