Mix beef, pork, 1 cup spaghetti sauce, and dry soup mix together in a bowl. Add bread crumbs and eggs; stir to incorporate. Divide meat mixture between two loaf pans.
Stir remaining 1 cup spaghetti sauce and condensed cream of mushroom soup together in a bowl.
Bake meat loaves in the preheated oven for 30 minutes. Pour cream of mushroom soup mixture over the top of each loaf and return to oven. Continue baking loaves until no longer pink in the center, about 30 minutes more. An instant-read thermometer inserted into the center should read at least 160 degrees F (70 degrees C).
You may want to reduce cooking time by 10 minutes if you make this into small loaves.