Cut 1 ½ pounds chicken breast breasts into 1-inch (2.5 cm) cubes. Place in a bowl and sprinkle with salt and ¼ teaspoon ground black pepper. Rub the meat with your hand to season all sides thoroughly.
Heat half of 2 Tablespoons lard in a saucepan over medium-high heat. Add the chicken cubes and fry until the meat gets a light brown crust on the surface. Stir carefully.
Remove the fried chicken from the pan and transfer to a bowl. Set aside.
Peel 1 large onion and chop it finely.
When the meat is cooked, browned bits will likely remain on the bottom of the pan. Reduce the heat and add two tablespoons of stock. Use a wooden spoon to scrape the bottom until the bits loosen.
Add the rest of lard, heat the pan over medium heat and add the chopped onion. Fry, stirring constantly, until lightly golden.
Reduce temperature to one-third. Stir in 2 ½ Tablespoons all-purpose flour and 1 Tablespoon sweet paprika powder. Stir and fry for about half a minute.
Remove the pan from the heat and pour in about a cup and a half of the chicken broth. Whisk immediately to prevent lumps from forming.
Add the rest of the broth (in total 2 ½ cups chicken broth) and stir. Cover with a lid and return to the stove. Increase the heat and bring to a boil. Reduce heat to low and simmer gently for 15 minutes. Stir occasionally as the flour tends to stick to the bottom.
Carefully pour the finished sauce into a mixing bowl. Using an immersion blender, puree until smooth. Add ½ cup heavy cream, ½ teaspoon sugar and ½ Tablespoon lemon juice. Season with salt to taste if necessary. Do not cook anymore!
Pour the creamy paprika sauce back into the saucepan and add the fried chicken breasts. Heat on low for about ten minutes and you are ready to serve!