1/16teaspooncalcium chloride, mixed in 2 tablespoons water before adding it to the cream
1/8 teaspoontartaric acid, mixed in 2 tablespoons water before adding it to the cream
Pour the heavy cream and milk into a small saucepan. Thoroughly stir in the calcium chloride mixture making sure it is fully distributed throughout the cream. Gently heat the cream over medium heat until it reaches 185-190 F, stirring constantly to prevent scorching. Use a dairy thermometer or an instant read thermometer.Once the cream reaches 185-190 F adjust the temperature so that the cream remains at 185-195 F and hold it at that steady temperature for 5 minutes.During the 5 minutes dilute the tartaric acid in 2 tablespoons of water. Stir in the tartaric acid mixture, stirring constantly for about a minute. The cream will curdle and take on a consistency of thin cream of wheat. Let it cool for 5 minutes.Pour the thickened cream into a colander that's lined with cheesecloth. Cover it to prevent anything from falling in it and place it in the fridge or in a cool place to let it drain for about 4 hours (or longer) until the desired consistency is reached. Transfer the mascarpone to a bowl. Cover and keep refrigerated. It will keep for 3-5 days. (See also section above about freezing mascarpone.) Makes about 2 cups of mascarpone cheese.Note: This recipe can be doubled.