Grind the pork shoulder through a large die into a bowl set in ice. Do not grind diced fat during this step.

Dissolve Fermento in just enough water, 1/4 to 1/2 cup (60 to 125 ml) to make a thin paste. Add to meat, along with other ingredients, including fat, and mix thoroughly by hand.

Pack the mixture in a pan or plastic container, and press out any air pockets. Cover with plastic wrap, pressing down so that it touches the meat and no air gets to it.

Refrigerate for 3 days. The mixture should have a nice red color to it after 3 days.

Regrind the mixture through the small die. Saute a small piece, taste, and adjust the seasoning if necessary.

Stuff the sausage into casings. I used inedible fibrous casings.

Hang on smoke sticks and let dry for 10 hours at room temperature (65 to 70 °F/18 to 21 °C). I have a digital temperature switch on my OBS so I hung them in the smoker to dry with the top vent completely open; with the temperature switch set at 65 °F.

After drying, cold smoke the sausages at the lowest possible temperature, ideally below 100 °F/37 °C for 5 hours. I used hickory bisquettes for the entire smoke. The color change after the cold smoke is amazing.

Raise the temperature of the smoker to 180 °F/82 °C and bring the sausages to an internal temperature of 150°F/65°C.

Transfer to an ice bath to chill completely, then refrigerate.

Optional: If using fibrous casings, I like to dip the sausages in boiling water to shrink the casings and then transfer them to an ice bath.