01 -
Tear the bread into rough pieces and place in a small bowl with the milk. Let soak for 5 minutes, then squeeze out the excess liquid firmly. Crumble the bread loosely into a large mixing bowl.
02 -
Add the ground pork, ground beef, egg, grated onion, 2 tablespoons of chopped dill, salt, pepper, and nutmeg to the bowl with the bread. Mix gently until just combined, avoid overworking. With damp hands, roll into balls about 1.5 inches (4 cm) in diameter, yielding 18 to 20 meatballs.
03 -
Melt 2 tablespoons of butter in a wide, heavy skillet over medium-high heat. Working in batches to avoid crowding, brown the meatballs for about 2 minutes per side. They do not need to be cooked through yet. Transfer to a plate and set aside.
04 -
Lower the heat to medium and add the remaining 1 tablespoon of butter to the same pan. Sprinkle in the flour and stir for 1 minute. Gradually pour in the chicken broth while whisking constantly to prevent lumps. Simmer for 3 minutes, stirring occasionally, until the sauce begins to thicken.
05 -
Return the meatballs to the pan, placing them into the sauce. Cover and cook over low heat for 12 to 15 minutes, turning once halfway through, until the meatballs read 160°F (71°C) on an instant-read thermometer.
06 -
Remove the pan from the heat. Stir in the sour cream, remaining 3 tablespoons of fresh dill, and lemon juice. Season with salt and pepper. The sauce should be silky and coat the back of a spoon. Serve immediately over mashed potatoes or egg noodles.