You also need:
In a large pot bring milk and buttermilk gently to 180°F without stirring. Strain the curd from the surface. Gather the cheesecloth around and squeeze it gently.
For drier ricotta bring temperature to ~200°F.
Homemade ricotta is best if served slightly warm. Ricotta can be refrigerated for up to 3 days.
Different uses for ricotta: