In a large bowl, combine prawns, lime juice, chili powder, garlic, and ginger. Season to taste with salt and pepper and allow to marinate for 15-20 minutes.

While the prawns are marinating, melt the butter in a large skillet. Add the prawns and cook, stirring occasionally, just until the prawns begin to turn opaque and soften up slightly, 4-5 minutes. Watch carefully as prawns can overcook very quickly. Transfer to a plate and set aside.

In the same skillet, heat the coconut oil over medium heat. Add in the cumin seeds, turmeric, and garam masala. Cook until the spices become fragrant, approximately 1-2 minutes.

Add the onions to the spice mixture and cook until the onions develop a bit of color, 4-5 minutes.

Pour in the crushed tomatoes and season to taste with salt and pepper.

Cook, stirring occasionally, until the mixture thickens slightly, 4-5 minutes.

Reduce the heat to low. Add in the yogurt and heavy cream. Cook gently for 4-5 minutes, then add in the prawns and any accumulated juices and continue cooking just until the prawns are heated through.

Serve over cooked basmati rice and garnish with fresh cilantro. Enjoy!