In a blender pulse the shallot, ginger, garlic, lemongrass, coriander and chili sauce until it is very finely ground like a paste. If you need to you can add a few tablespoons of water to help it blend. In a small sauce pot sauté the paste with a little bit of coconut oil until it is aromatic. Whisk in the the coconut milk. Let the sauce gently simmer for ten minutes then turn off the heat.