Pour both kinds of milk into the Instant Pot. Lock the lid in place; turn the pressure release valve to seal. To pasteurize (heat the milk to 180°F), choose Yogurt and press Adjust until Boil appears on the display. When done, about 25 minutes, unlock and remove the lid.

For thicker yogurt, encourage evaporation: Press Yogurt and Adjust (or use Saute and Normal mode) to hold the milk at 180°F for 5 to 8 minutes. (Don’t expect boiling, unless you mistakenly have it at More, like I did!) If you like, use a meat or candy/deep fry thermometer to occasionally gauge the temperature at the center.

Cool the inner pot of milk in a sink filled with 3 or 4 inches of water. Or, use an ice bath: fill a large bowl or wide pot with 8 to 10 ice cubes and water to a depth of about 3 inches. Let the inner pot of milk sit in the cold water for about 10 minutes; frequently lift and swirl the pot to aerate and cool. When the milk hovers around 110 to 115°F, remove the pot from the water and dry the outside. Discard any milk skin that may have formed.

Ladle ½ to ¾ cup of warm milk into the yogurt and combine well. Stirring the warm pot of milk with the ladle, pour in the thinned yogurt. Replace the inner pot in the Instant Pot.

Lock the lid in place (the pressure release valve can be in either position). To incubate, press Yogurt, then set the time between 8 and 10 hours (use the maximum for tangy yogurt). When done, the display says “Yogt”. (Once set, I’ve let the yogurt sit in the IP) for several hours. The IP’s Yogt mode defaults to standby so no heat is on and the yogurt cools.)

Remove the lid. Whisk the yogurt for a consistent texture, avoiding the bottom where there’s likely a film of milk. For a thicker texture, strain the yogurt through fabric (set it in mesh strainer positioned on top of a bowl).

Transfer into containers or jars and refrigerate for about 2 weeks.