How to Make It
Combine milk, cream, and salt in a large saucepan. Heat over medium-high, stirring every few minutes to prevent scorching, until milk just begins to boil (milk will foam and begin to rise), 12 to 15 minutes.
Remove from heat and let stand until foaming subsides, about 30 seconds. Slowly stir in vinegar. Let mixture stand until milk curdles and separates from whey, 10 to 15 minutes.
Line a fine-mesh sieve with a double layer of damp cheesecloth; set over a large bowl. Pour curdled milk into sieve. Let drain, emptying bowl if bottom of sieve touches any drained liquid (the whey), until most of the whey has drained and a rich, creamy ricotta remains, 10 to 15 minutes.