Combine the cream, milk, sugar, vanilla, and salt in a large bowl. Whisk to combine. Pour into the ice cream maker and churn according to the manufacturer's instructions.
When the ice cream finishes churning, scoop into an airtight container, sprinkling M&M candies over each scoop. Do not stir much, as the candies will immediately begin to melt into the ice cream.
Serve immediately for soft serve ice cream or transfer to an airtight container and store in the freezer until ready to serve.