How to Make It
Combine 1 can of coconut milk, the brown sugar, and the salt in a medium saucepan. Set over medium-high heat and bring to a boil, stirring occasionally so that the sugar dissolves. Once boiling, reduce the heat slightly and continue to cook until the mixture has darkened and reduced, about 20-30 minutes. It should be very thick–resembling caramel. Add the second can of coconut milk to the warm coconut caramel and stir to combine. Meanwhile, beat the egg yolks in a large, heatproof bowl. Slowly whisk 1 cup of the hot caramel mixture into the bowl with the egg yolks.
Turn the heat to low and pour the tempered yolks back into the pot. Cook, stirring constantly, just until the mixture thickens, 1-2 minutes. Remove from the heat and pour into a bowl. Stir in the vanilla extract. Cover tightly and refrigerate until completely cool.
Pour the mixture into an ice cream maker and process according to manufacturer’s instructions. Freeze for at least 4 hours before serving.