Heat milk slowly to 86°F. If using calcium chloride, dilute 1/2 tsp in 1/4 cup water and mix in.
Sprinkle C101 culture over the milk, rest 2 minutes, mix in, and ripen 45-60 minutes. For raw milk, the source recommends half the culture amount.
Dilute rennet in 1/4 cup non-chlorinated water, mix in for 1 minute, and set 45 minutes.
Cut curd into roughly 1/4- to 3/4-inch pieces. Gently stir while heating to 102°F over 30 minutes, then hold at 102°F and stir another 30 minutes. Settle 20-30 minutes.
Drain curds into a cloth-lined colander. Keep warm in a pot set in 95-100°F water. Turn the curd mass every 15 minutes for 2 hours; after 1 hour cut it in half and stack the halves.
Mill the curd into 1/2- to 3/4-inch pieces. Over 30 minutes, add cheese salt equal to 2% of curd weight in three additions, allowing it to dissolve between additions.
Transfer to a cloth-lined mold. Press 10 lb for 15 minutes; flip and press 12 lb for 30 minutes; flip and press 20 lb for 1 hour; then 50 lb for 4 hours and 50 lb for 24 hours.
Dry 1-3 days, then wax or cloth-bandage. Age at 55°F and about 85% humidity for 3-9 months, turning daily for 8-12 weeks and then twice weekly.