01 - Heat coconut oil in a large pot over medium heat. Add onion and sauté for 3-4 minutes until translucent and softened.
02 - Stir in minced garlic and grated ginger, cooking for 1 minute until fragrant, being careful not to burn.
03 - Add sweet potato cubes and diced red bell pepper. Sauté for 2 minutes, stirring constantly to coat with oil.
04 - Sprinkle in curry powder, cumin, turmeric, and cayenne if using. Cook, stirring continuously, for 1 minute to release essential oils and enhance flavor.
05 - Pour in diced tomatoes with their juice, coconut milk, and vegetable broth. Stir thoroughly to combine all ingredients and dissolve any spice clumps.
06 - Bring to a gentle boil, then reduce heat to low. Cover and simmer for 18-20 minutes, stirring occasionally, until sweet potatoes are fork-tender.
07 - Add chopped spinach to the pot and cook for 2-3 minutes, stirring until wilted and evenly distributed throughout the curry.
08 - Stir in fresh lime juice and adjust seasoning with salt and pepper to taste. Serve hot, garnished generously with fresh cilantro.