In a small bowl, grind together garlic, onion and ginger. In a separate small bowl, mix together curry powder and 5 tablespoons water.
Heat oil in a large skillet over medium high heat. Saute garlic, ginger and onion until browned; add curry paste and saute together until smell is strong and fragrant.
Add yogurt, coconut milk and regular milk along with 1 cup of water, and stir all together. Then add potatoes and chicken and bring to a boil; reduce heat and simmer until potatoes are tender and chicken is cooked through, about 20 to 25 minutes.
Season with salt to taste and simmer for another 2 minutes; the curry is ready!