Puree shallot, salt and macadamia nuts in a food processor until fairly smooth.
Melt butter in a pan over high heat and add shrimp. Saute one minute then add shallot-macadamia mixture. Stir the shrimp several times while they continue to sauté for three more minutes. Add coconut milk to the shrimp and cook one minute more.
Remove from heat and squeeze a generous amount of lime juice on top to taste