Yes, you can make a delicious pasta sauce using coconut milk if you choose the right product. Use coconut cream instead, which has a fat content of around 20%, since heavy cream is more like 36% or more. They are similar in terms of richness and creaminess, but you can still expect a lighter sauce. Light coconut milk that comes in a cartoon (less than 5%) or in a can (around 15%), is nowhere near that. Hence, they are not good substitutes for making pasta sauce.