Preheat oven to 350℉. Rip bread into small pieces and place in a bowl. Cover with cream. Set aside.
Meanwhile, melt 1 tsp of butter in a skillet over medium heat. Add onion and garlic cook until brown, about 10 minutes. Remove from the heat.
Lightly miix together the ground beef, pork, egg, salt, pepper, nutmeg, allspice, onion, and garlic in a bowl. Pinch off about 1½ tbsp of the mixture and form into a ball. Place on a plate until all are formed.
Place the meatballs into a skillet over medium high heat. Add the meatballs, turning often and cook until browned, about 5 minutes.
Place the seared meatballs into a baking dish with a little broth (about ½ cup) and cover with foil. Cook in the oven for 20 minutes.
Add the baking dish drippings into the pan with the butter. Add flour and whisk to combine. Slowly add the beef broth, stirring continuously. Bring to a simmer and reduce the heat to thicken, about 5 minutes.
Taste and add salt and pepper if necessary. After it's thickened, mix in the sour cream. Add the meatballs back in to be coated in the sauce. Serve with ligonberry jam.