Here's where you introduce the other proteins and textures. An important part of making a good terrine is making sure there isn't one uniform texture. The duck breast is cut into 1/2 inch cubes, so you need to take the pork in a different direction.
Cut 1 lb of pork shoulder and 3/4 lb fatback into 1/8" sheets, then cut those into 1/8" cubes. Try to keep your protein cold, it cuts easier.
I was using a long knife that I felt to be my sharpest but it just seemed slow and not accurate. I had to switch partway through to my Santoku-style knife and it was much better. This step takes a long time if you aren't chopping stuff for precision on a regular basis (i.e. Me).
After you cube your meat and fatback, make sure to completely chill the meat, then on a cutting board run your chopping knife through it several times to get an even smaller chop and texture. It should be something like ground hamburger.
Then finely chop two cloves of garlic and put them in a food processor with 1/4 lb chicken liver and pulse until you get a nice pureƩ (this is the third texture for your terrine).
Then put in even spoonfuls of the pork shoulder and fatback and pulse twenty times until incorporated. Put in a mixing bowl. Continue to pulse batches of the pork and fatback until it is all done.
Add two eggs, 1 Tb chopped, fresh thyme, 1/2 teaspoon ground cloves, 1/2 teaspoon ground ginger, 1/4 teaspoon ground nutmeg, 1/4 teaspoon paprika, and 4 and 1/2 teaspoons kosher salt. Mix with hands until everything is evenly incorporated.
Pan fry a test batch (about a tablespoon full) about 2 minutes on each side and taste for flavor. Adjust seasoning accordingly. This is a very important step because you might have forgotten something. Like salt. Phew! Cover and put in fridge for a minimum of one day and up to three days for the flavors to meld.