Pour the raw milk into the instant pot. Press the Sous Vide button and set the temperature to 86℉. Set the time to 4 or more hours. (* see notes)
Once the pot reaches 86℉ (there will be a single quiet beep when it does this), sprinkle half of the culture onto the milk and stir well. Let the pot sit for 45-60 minutes.
In a separate small bowl, dissolve the rennet in a ⅛ cup of water.
After 45-60 minutes, pour the dissolved rennet into the milk and stir well. Let this sit for 30-45 minutes.
The curds will be ready to be cut when the curd forms a clean break (**see notes)
Once the curds are cut into a grid pattern, cover the pot and press cancel. Press the sous vide button again and set the temperature to 102 ℉ (time should be set to 2+ hours).
Let the pot warm up. Then, once its reached 102°, let it sit for another 30 minutes. Stir the curds occasionally throughout this time.
After 30 minutes, the curds will have sunk towards the bottom of the pot. Scoop them into a colander/strainer and sit the colander overtop of the pot of whey. The whey should not be touching the colander, but instead be steaming the curds.
Leave the pot of whey at 102℉, cover the pot, and let it sit for 60 minutes. During this time, flip the curds over a couple times.
Then remove the curds and cut them into strips. The strips should resemble the size of a thick cut French fry (at least a centimeter thick).
Toss the curds in a bowl with salt until the curd is thoroughly coated. You can now eat the fresh curd or press and age the cheese to get a traditional cheddar.