In large skillet, heat oil over medium heat. Add onions, ginger and garlic; sauté 3-5 minutes or until onions are tender.
Add in lamb; cook and crumble until cooked through. Add in potatoes, coriander, cumin, cayenne and salt. Sauté 1 minute. Stir in tomato sauce; reduce heat and simmer 6-8 minutes, stirring occasionally.
Stir in spinach; continue simmering 15-20 minutes or until potatoes are soft, stirring occasionally.
Remove from heat; stir in whipping cream and Garam Masala.
Serve with cooked basmati rice and Naan, if desired.