In a medium saucepan, combine 1 cup of the coconut milk with the cocoa powder. Warm over medium-high heat, whisking to dissolve the cocoa. Bring the mixture to a boil, then reduce the heat to medium-low and let simmer for 30 seconds, whisking constantly. Remove the pan from the heat, mix in the chocolate and whisk until melted and smooth.

Stir in another 1 cup of coconut milk. Transfer this mixture to a medium-large mixing bowl. Set a fine mesh sieve over the top.

In the same saucepan, combine the rest of the milk, sugar and salt and warm the mixture over medium-high heat.

In a medium mixing bowl, whisk together the egg yolks. When the milk mixture is warm, gradually whisk the milk into the egg yolks, beating constantly.

Return the egg-milk mixture to the saucepan and continue heating over medium-high heat, stirring constantly and scraping the bottom of the pan with a spatula, until the mixture is slightly thickened and coats the back of a spoon. Remove from the heat, pour through the mesh sieve into the chocolate-cream mixture and stir to blend. Stir in the vanilla.

Cover with plastic wrap and chill the mixture in the refrigerator for several hours or overnight. Once the ice cream mixture is well chilled, freeze in an ice cream maker according to the manufacturer’s instructions.

After it finishes churning, layer ice cream with hot fudge sauce, starting with hot fudge sauce. Do not swirl the two together. Freeze until hard before serving.