Swedish meatballs

Breadcrumbs, fresh	1 cup
Stock, beef	1/3 cup + 2 cups
Butter, unsalted	1 tablespoon + 1 tablespoon + 1 tablespoon + 1 tablespoon
Onion, minced	1 cup
Bacon, minced	2 slices
Beef, ground chuck	1 pound
Pork, ground	¾ pound
Eggs, lightly beaten	3 large
Salt, kosher	1 tablespoon
Pepper, freshly ground	1 ½ teaspoons
Sugar	1 ½ teaspoons
Allspice, ground	1 teaspoon
Nutmeg, freshly ground	½ teaspoon
Flour, all-purpose	2 tablespoons
Sour cream, whisked	2 tablespoons

1. Mix the breadcrumbs and 1/3-cup stock in a small bowl; set aside. 
2. Melt 1-tablespoon butter in a medium skillet over medium heat. 
3. Add the onions, and sauté until browned, about 10 minutes; transfer to a large bowl. 
4. Wipe out the pan, and return to medium heat. 
5. Add the bacon, and cook until crispy; using a slotted spoon, transfer the bacon to the bowl with the onion; reserve the bacon fat. 
6. Add the beef, pork, eggs, salt, pepper, sugar, allspice, and nutmeg to the bowl, and mix using your fingers. 
7. Fold in the breadcrumb mixture. 
8. Using a 1-tablepsoon scoop, roll the meat mixture into balls; transfer to a rimmed baking sheet. 
9. Melt 1-tablespoon butter with the reserved bacon fat in a large heavy pot over medium-low heat. 
10. Working in batches, and adding 1-tablespoon butter between batches, brown the meatballs on all sides, about 6 to 8 minutes per batch; transfer to a plate. 
11. Drain all but 2-tablespoons drippings from the pot. 
12. Whisk in the flour until a smooth paste forms. 
13. Stir in 2-cups stock; bring to a simmer, whisking often. 
14. Return the meatballs to the pot. 
15. Cover; simmer until meatballs are cooked, about 5 to 6 minutes. 
16. Remove from heat, whisk in the sour cream, and stir to coat the meatballs. 
17. Serve with noodles and lingonberry sauce.