Heat butter (2 tbsp) in a saucepan. Sautee the onions (2) until transluscent, 2-3 minutes. Add garlic cloves (4) and ginger (1 inch) and sautee 1 minute until fragrant. Add turmeric (1 tsp), cumin powder (1 tsp), paprika (1 tsp), and garam masala (1 tsp). Sautee until fragrant.
Add lentils (300g). Pour vegetable broth ('780ml`), bring it to a boil, and reduce to a simmer. Simmer for 10 minutes or until lentils have absorbed the liquid.
Add coconut milk (240ml) and chopped tomatoes (100g). Season with salt, pepper, lime juice, and coconut sugar to taste.