12 oz ground beef
12 oz ground pork
1 egg
1/4 cup milk
1/3 cup bread crumbs (I use panko)
1/4 cup grated onion (I use my box grater)
1 tsp salt
1 tsp brown sugar
1/4 tsp nutmeg
1/4 tsp allspice
1/4 tsp pepper
2 tbsp vegetable oil
Sauce:
1 tbsp butter
1 tbsp olive oil
1/4 cup + 1 tbsp flour
3 cups beef broth
1 tsp brown sugar
1/2 cup sour cream
Mix ground meats, egg, milk, bread crumbs, onion, salt, brown sugar, nutmeg, allspice, and pepper. Heat 1 tbsp oil in skillet over medium heat. Roll half of meat mixture into 1-2" balls and brown on all sides (don't cook completely), then drain on paper toweling. Add 1 more tbsp oil, then finish rolling, browning and draining rest of meatballs.
Heat butter and olive oil. Stir in flour until browned and slightly crumbly, stirring constantly. Slowly whisk in broth 1/2 cup at a time until thick and smooth. Stir in brown sugar and bring to low simmer. Add meatballs and cook for 10 minutes, stirring occasionally to cover with sauce.
Ladle 1/2 cup sauce into small bowl and whisk in sour cream. Add back to meatballs.