4 cups (1 liter) whole milk 
(or coconut/almond milk for dairy-free) 2 tbsp plain yogurt (with live active cultures)
That’s it! Just 2 ingredients!
Tip: Use a high-quality store-bought yogurt with live active cultures to start. After your first batch, you can use homemade yogurt as a starter for the next batch!
Step-by-Step Instructions
Heat the Milk
