Heat the coconut oil in a large deep skillet over medium heat. Add the ginger and garlic and cook, stirring often, until golden brown, about 5 minutes; season with a pinch of salt. Add the curry and tomato paste and cook, stirring, for 2-3 minutes.
Add chopped tomatoes and cook, until slightly thickened, about 5 minutes. Stir in coconut milk and season with a pinch of salt. Bring to a boil, then reduce to heat to medium-low and add the sweet potatoes.
Seeding and removing the pith and ribs of a fresh red chili pepper will make it less spicy.