Melt butter in a large pot over medium heat. Add onion, fenugreek, cumin, coriander, salt and pepper. Cook for 3 minutes until onion is softened but not golden.
Add garlic and ginger, cook for 2 minutes.
Add the tomato and chilli, cook for 3 minutes on a medium heat.
Add about ⅓ of the spinach and stir until wilted. Then add more spinach along with the water, cook again until wilted. Repeat until all the spinach is wilted.
Cook, stirring every now and then, for 10 minutes still on a medium heat.
Add the cream and lemon juice. Cook, stirring gently, for 3 minutes.
Remove half the spinach into a tall container and blend it to a puree using a stick blender. Pour pureed spinach back into the pot, and stir to combine.
Gently stir in golden pan-fried paneer. Stir gently to mix through.
