Preheat Oven: Preheat the oven to 325 degrees F and add the rack to the center.
Prep Onions: Melt 1 tablespoon of butter in a sauté pan. Add the onion and cook for 2-3 minutes until the onions are soft. Add them to a large bowl.
Prep Breadcrumbs: Add breadcrumbs to a medium-sized bowl. Add milk, starting with 1/4 cup and use just enough to wet all of the bread. Add a bit more if all of the bread is not wet, but don't use more than 1/3 of a cup. Set aside.
Make Meatballs: Add the meats to the large bowl with the onions and add the parsley, egg, salt, ginger, and nutmeg. Mix well and then add the milk-soaked bread crumbs. If there is any extra milk in the bowl with the bread, do not add. Add the meat mixture to the fridge for at least 15 minutes to cool. This will help make shaping the meatballs easier. Shape Meatballs: Shape the meat into 2 - 3ish inch meatballs and add to a rimmed baking sheet. Don't worry about crowding.
Bake: Bake the meatballs on the middle rack for 30 minutes.
Baked Meatballs: Once the meatballs are done, remove them with tongs and add them to a plate or bowl to set aside. Then use a spatula to scrape all of the drippings from the baking sheet into a large pot or Dutch oven.
Make Gravy: Heat the pot with the drippings over medium heat and add 2 tablespoons of butter to the meatball drippings. Add the flour and whisk it with the butter to create a roux. Slowly add beef broth, mixing the roux with it as it's added until all the broth is incorporated. Add instant coffee.
Add Meatballs to Gravy: Add the meatballs to the pan and let them simmer on medium-low for 15-20 minutes.
Serve and Enjoy! Serve over noodles, rice, or whatever you'd like!