Which has a better outcome- pre-frying meatballs then adding to sauce or simply cooking in the sauce.
I bake my meatballs on parchment paper at 425 for 15-25 minutes, depending on their size (I generally make small ones, so it's 15 minutes), and then add to sauce. I always make 3-4 pounds of meat, freeze, and then add to sauce as I use them.
It depends on what you're going for (and how many pans you want to clean!) I have both baked them as Phyllis does, or added them directly to the sauce. If you bake them or pan fry them, they may have a nicer browned exterior, and adding them to the sauce can cause them to fall apart. But it is also nice to have them sort of absorb the sauce, especially if you don't mind one or two falling apart a little.
I prepare my meatballs with a 2 oz. disher to make sure they are all uniform sizes, then put them on a wire rack over a tray and bake them at 350 until they hit about 160 degrees. Then I add them to the sauce. The wire rack lets all the fat that otherwise would pool or stay with the meatballs drop through and land on the tray, then I wipe the tray down and wash it.
I pan sear them first, let them get a nice crust, and then when they've cooked about halfway, add my sauce to the pan and cover. I find this helps them hold up and still absorb the flavor of the sauce.
If you don't brown them first, you will lose a lot of flavor.
I was a brown, then simmer person for years ... until I was lazy one day and just let the balls simmer in a simple tomato sauce - it added a depth of flavor that was incredible. Try it!
I prefer to brown or bake meatballs before adding them to sauce because I think cooking them at least partway gives them more depth of flavor. I also like meatballs to have a browned and caramelized exterior, which you can't get if you are cooking meatballs from beginning to end in the sauce.
I confess to nuking them until halfway done, adding the resultant juices to the tomato sauce and let them simmer from there ...
I start my sauce and while it's cooking to a nice hot temp, I make the meatballs. I then add them directly into the hot sauce. I usually add pork and/or pepperoni to my sauce and the meatballs take on more flavor. Unless you stir your sauce vigorously, the meatballs are not going to break. They come out tasty and tender.
Just a tip. Your meatball do not need to be 160 that is for chicken or re heats. Beef starts at 145 to be safe You can put them at much lower than that or raw. Being in the gravy will certainly bring them way past 165. The difference is that they are cooking in the sauce so it tenderizes them.