Swedish Meatballs recipes

Name: Swedish Meatballs recipes
Ingredients: 2 Tbsp butter; 1 large yellow or white onion, peeled, grated (use the large holes of a box cheese grater); 2/3 cup milk; 4-5 slices of bread, crusts removed, bread cut into pieces; 2 eggs; 1 pound ground pork; 1 1/2 pounds ground beef; 2 teaspoons kosher salt; 1 teaspoon freshly ground nutmeg; 1 teaspoon ground cardamom; 2 teaspoons black pepper; 6 Tbsp butter; 1/3 cup flour; 1 quart beef stock; 1/2 to 3/4 cup sour cream; salt; 2 to 4 Tbsp of Lingonberry, red currant, raspberry or cranberry jelly, less or more to taste (optional)