1) Heat butter in a pan. Then add onions and fry until translucent. Add ginger paste and garlic paste and saute for 2 minutes. Add lamb or mutton, salt, cumin, black pepper and chilli. Fry until light brown. Then add coriander/cilantro leaves and mix. Remove from heat and let cool.
2) On one slice of buttered bread arrange the mutton mixture and top with Spinach and cheese. Cover with another buttered slice of bread.