Loo, you have more courage than I have in tackling this subject. What I mean about that is I don't think it can just be about Malnati's sausage without many people hitting onto all the various sensitive opinions, thoughts, etc. about pizza sausage in general. "OH, THAT"S NOT ITALIAN SAUSAUGE (of my youth) THAT I KNOW!!!" To that I say, yeah, happy HS.
This follows up somewhat on the discussion started on at http://www.pizzamaking.com/forum/index.php/topic,7302.0.html
Here's my story . . . and I'm sticking to it. I grew up in the south side of Chicago and came to fall in love with something called pizza "pie" in the late 50's (it was always called "pie"). On one block where I lived, the kids rode on their fancy Schwinn bicycles and spoke Italian. On the next block, they rode J.C. Higgins bicycles and spoke Polish, and on the next block the kids spoke German, and on the next block spoke, Yiddish, etc. And in time, we all got together, spoke our broken English, and played 16" softball together. When talking about 16" softball, does anyone outside the Chicago area know what the hell I am talking about? ? ? Probably not.
Regarding sausage, the prime influence on pizza sausage and sausage in general in the Chicago area were the Italians and the Poles. When you looked at it closely, one would see that there wasn't that much difference in their sausage formulations; the Poles emphasizing Garlic and the Italians emphasizing other Italian spices, some even with fennel. Even today, many eating at all the various great pizzerias in Chicago wonder if they're eating a pizza with Italian or Polish sausage. I -- with a preference on thin crust pizzas for sausage with fennel-- swear that the majority of sausage at Italian pizzerias are with "Polish" style sausage (little to no fennel and more garlic than not).
Italian sausage and Polish sausage and Lithuanian sausage -- and others -- all got combined in many respects over time in the Chicago metropolitan area. Some Italian deli's made their sausage with fennel seed, usually crushed, as opposed to uncrushed, many did NOT use fennel at all (contrary to the experience of many in the NY area). Most Polish and Lithuanian deli's used various degrees of garlic in their sausage recipes. But contrary to remarks made herein, whoever said there is no garlic in Italian sausage is . . . whistling Dixie. The majority of the many, many, many recipes for making Italian sausage have in fact included . . . garlic in its recipe. Not all recipes to be certain, but many (or maybe even most) include garlic. Let me know if one needs leads to websites to show this.
My sister, when alive, was a great, great sausage maker. I am not. For pizza sausage, I think she would advise me to first, ensure the pork shoulder was Coarsely ground, as opposed to be ground like hamburger meat. She would say that finely ground pork is no where close to great sausage. Following on Marc Malnati's remarks, I can definitely picture the combination of Italian and Polish and Slavic influence in determining the type of sausage to use on early day "deep dish" pizza in the Chicago area in the era or the 1940's and 50's. Garlic would have been the predominant influence and not fennel (or anise). Not for one second am I saying that I don't like fennel or anise spices in my pizza sausage. Just not in classic Chicago deep dish style pizza.
So in looking at many types of formulations, here's what I vaguely remember from my sister on a style of sausage that may be close to a Malnati's style:
3 lbs. Ground Pork Shoulder (80/20 -- but I do prefer a leaner proportion with good meat)
2 T Morton's Kosher Salt
1 T Fresh Ground Black Pepper
1/2 cup ice cold water
2 cloves garlic, crushed in press (or some powdered equivalent)
1/2 t marjoram
1 to 1/2 t Sugar
1/2 t dried thyme
1/4 t dried basil
1/2 t onion powder
1/4 t ground coriander