In a large bowl, combine the ground beef, Allspice, Tarragon, Garlic Powder, Salt, Pepper, Parsley, bread crumbs, parsley, onion, and egg. Mix until evenly distributed and well combined.
Spray or line a sheet pan and begin to roll out your meatballs. Remeber, Swedish meatballs are smaller than the ones we are normally accustomed too. Start with one heaping tablespoon of mixture. Meatballs should be about 1-1/2 inches round. Roll out meatballs until there is no mixture left in the bowl.
Preheat your skillet with 2 tablespoons of butter and the olive oil. Starting on the outside edge of the pan, place your meatballs in a circular pattern, working inward, and leaving 1 to 1-1/2 inches in between each meatball. Cook, turning each meatball until browned on all sides. Once meatballs are browned and cooked through, remove and set aside.
In the same pan, add in the butter until melted. Once melted, whisk in the flour until a thick roux is formed. Cook for 1 minute to allow the flour taste to "cook-out".
Whisk in your beef stock and heavy cream and allow the mixture to come to a simmer. Once at a simmer add the salt, pepper, and Tarragon.
Place your meatballs back in the pan, coat with the gravy and allow to simmer for up to 15 minutes.
Garnish with fresh parsley and Lingonberry jam and serve!