Pour whole milk, cream, salt and acid in a heavy-bottomed stainless steel sauce pot. No need to stir or mix ingredients together. Place pot on stove over medium-high heat and wait for mixture to boil.
Meanwhile, place a strainer lined with cheesecloth over a medium bowl and have a slotted spoon ready.
Once mixture has come to a boil, remove pot from heat and let it sit undisturbed at room temperature for 15 minutes. At this point the mixture should start to coagulate and thicken.
Use a slotted spoon to scoop up the formed cheese curds. Gently transfer cheese curds to prepared cheesecloth. Do not simply pour the mixture into the strainer. You do not want to break up the curds that have formed.
Once you have scooped up all the curds, tie up the cheesecloth into a pouch. You can adjust the moisture of ricotta to your liking depending on how tight you tie the pouch. Looser tie means wetter ricotta, tighter tie means drier cheese. (I prefer dry) At this point the ricotta will be warm. You can use it immediately or store in the fridge to cool down and firm up. (I prefer the latter.)