Combine the milk, mayonnaise, cream, sugar and coffee in a medium saucepan. Whisking, bring to a simmer over medium heat and cook until thickened, 4 to 5 minutes. Remove from the heat, add the chocolate chips and vanilla, and whisk until the chocolate is fully melted. Divide evenly between six 4-ounce mason jars. Chill in the refrigerator until set, about 3 hours. Garnish with berries and serve.
Recipe courtesy of Damaris Phillips