If you’d like a redder sauce that looks closer to traditional tomato sauce, you can add extra beet juice (reserved from the can) a tablespoon or so at a time until the color is deeper. Please note that the more beet juice you add, the stronger the beet flavor will become. Personally, I prefer a less pretty color with less of the beet flavor, but the choice is yours! To get the color you see here, I added a total 1/4 cup / 60 ml of additional beet juice.
Adding the pancetta or bacon helps increase the fat content for a juicier meatball. If you can’t find pancetta, you can use bacon but smoked bacon will add a noticeable smoky flavor to the meatball. If you’d rather not have that smokiness, use an unsmoked bacon, if possible.
Standard grocery store ground pork is way too lean for this. You’ll want to use a fattier ground pork, like the kind that’s used to make sausage. Something like ground pork shoulder like my grocery store uses to make their sausage would work well. If you can’t find pork like this, you can make the meatballs with all ground beef, preferably at least 20% fat.