Heat 1 quart of milk in a pot over medium heat until it is hot but not boiling
Stir in 2 to 4 tablespoons of lemon juice or white vinegar
Let the milk sit for 5 to 10 minutes until curds form and whey separates
Line a strainer with cheesecloth and place it over a bowl
Pour the curds and whey into the lined strainer
Let the whey drain for 10 to 30 minutes, depending on desired texture
Gather the cheesecloth and gently squeeze out excess liquid if needed
Transfer the curds to a bowl
Add salt to taste if desired
Use immediately or refrigerate in a covered container