In a large pot or deep skillet, heat the coconut oil over medium heat until it shimmers.
Add the diced onion and sauté for about 5 minutes, until translucent.
Stir in the minced garlic and grated ginger, cooking for an additional minute until fragrant.
Sprinkle in the curry powder, ground cumin, turmeric, garam masala, and chili powder (if using). Stir continuously for about 30 seconds to toast the spices.
Add the diced potatoes to the pot, stirring to coat them with the spice mixture.
Pour in the coconut milk and vegetable broth. Bring the mixture to a gentle simmer.
Cover the pot and let it cook for about 15-20 minutes, or until the potatoes are tender when pierced with a fork.
Once the potatoes are cooked, stir in the green peas and season with salt. Allow to cook for an additional 5 minutes.
Remove from heat and stir in the lemon juice for a bright finish.
Serve hot, garnished with fresh cilantro.