Heat cream, half-and-half and vanilla in a saucepan until it comes to a simmer. When it begins to simmer, immediately take it off the heat.

Add sugar and salt to the heated liquid and stir until the sugar is dissolved. This will only take about a minute. (You can taste the ice cream batter at this point and adjust the sugar and/or salt to your taste. Be advised, though, that the batter should taste very sweet. It will mellow as it is churned and frozen in your freezer.)

Refrigerate the batter for several hours until it is very cold.

Prepare in your ice cream maker according to your manufacturer's instructions. Serve immediately or put into an airtight container and freeze until the ice cream is hard.