Peel 2 small onions and chop them roughly. Salt 4 chicken thighs from all sides.
In a wide, thick-bottomed pan, melt 1 Tablespoon pork lard over high heat. Place the chicken in the pan and fry each side for about 5 minutes. Remove the chicken and set it aside.
Reduce the heat to medium. Add the chopped onions to the same pan and fry until they become translucent. Use a flat-edged spatula to scrape the browned bits from the bottom of the pan, as they are very flavorful and should be included in the chicken paprikash.
Add 2 Tablespoons ground sweet paprika and stir for 30 seconds.
Pour in 2 cups chicken broth and return the fried chicken pieces to the pan. Throw in the 5 allspice berries. Bring to a boil, then reduce the heat to low. Cover with a lid and allow the paprikash to simmer for 40 minutes, or until the chicken meat is soft and tender.
Remove the cooked chicken and set it aside, keeping the meat warm.
Make a roux: In a non-stick pan, melt 1 Tablespoon (heaped) unsalted butter over medium heat until it starts to bubble. Sprinkle in 1 Tablespoon (heaped) all-purpose flour and fry for 1-2 minutes while stirring. Gradually add the roux to the paprikash, whisking thoroughly to avoid lumps.
Cover with a lid and let the sauce simmer for 15-20 minutes.
Remove the pan from the heat source and add 3/4 cup sour cream. Stir well, but do not cook any further.
Strain the paprikash through a sieve, discarding any remnants caught in the sieve, such as onions and allspice berries.
Season the paprikash with salt to your liking. Optionally, add 1/2 teaspoon granulated sugar
Put the chicken pieces back into the pan, let them warm up in the sauce, and then serve.