Southsidermike,
I'll be making some Italian Sausage this weekend, too. The recipe is my Italian MILs. But, she'd never heard of fatback and I was determined to find and add it. I also make an excellent breakfast sausage that I make very similarly, but with different spices.
The first time we found a pearly while block at a European market...labeled in Polish. We took a chance. She didn't want to use it. So, I ground it all and added it some. I had some left and she put it in hers. Later, she said it was the best sausage she'd made.
I do think it does make a difference. Her sausage was always great, but this really did give us better taste and a bit more fat, making it juicier. We leave out some of the hard fat from the butt as it can be chewy or leave hard bits. So, we need some of this to make up for what we take out. This really does make a difference for us. Some people would never care. And some people prefer the harder fat because it's more typical and offers some chewiness. Our family dislikes any form of hard pieces, gristle, etc., so for us, this is necessary, lol. The family has names for them like yanks and shanks and goombas, lol. When we buy other sausage, someone is always complaining about what they find.
I have purchased the fatback at several other places. The best was that European market (I can't remember which one...wish I could); the worst is at one of my favorite meat places, Paulina. Here lately comes pre-ground in 1 pound packets; the pieces are little chunks, maybe 1/4"x1/4". In years past, it came in blocks, but not the last time. This didn't grind in the grinder --it sort of just went right through and came out about the same--so I mixed it in thinking it would melt when fried. But, it didn't; it let left little chunks of fat and some of them aren't soft, but are chewy. It was OK in the Italian - maybe because it cooks longer - but not in the breakfast sausage.
I've also gotten fatback at a Mexican market. I found the term on here and wrote it down and took it with me. Another place I was successful was the meat market on Cicero - maybe around Belmont? I can't remember, but I found it listed on here. I called ahead of time and he kept it set aside for me. It worked about as well as the first place I found it.
To the mix, I have been a bit meticulous to find out the right mix. When I cut up the meat, I put it in several piles: all/mostly lean, 50% mix of lean and fat, all/mostly fat, then the hard fat that I don't use. My MIL is also meticulous about cutting. She cuts out every oddity found. Veins, discolorations, you name it, it comes out. It takes us a long time to cut it like this.
Then I grind it up by type - all the lean in one bowl, all the fat in another, etc. I add some fatback to the fat bowl before I grind it. I weigh it out and then mix it based on the blend I want of fat and lean. Too lean is just too healthy. It's dry and icky. Too much fat and none of us like it. I can't find my notes on the Italian, but for the breakfast, we use 4 parts lean, 2 parts 50/50, and 2 parts fat. I seem to think the Italian is about the same, but maybe a bit more lean?
You may have already made it or wish to do it differently.
Cevapcici is another tasty, easy sausage to make while you are grinding

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