Start by combining ground chicken, almond flour, parmesan, egg, garlic, parsley, salt, and pepper in a bowl. Mix gently until everything is just combined without overworking the meat. Overmixing can make the meatballs dense instead of tender.
Using your hands or a small scoop, form the mixture into evenly sized meatballs. Try to keep them uniform so they cook evenly. Place them on a plate or tray while you prepare to cook.
Heat butter in a skillet over medium heat and add the meatballs in a single layer. Cook until they are golden brown on all sides, turning occasionally. This should take about 8–10 minutes.
Once the meatballs are browned, remove them temporarily from the pan. Add chicken broth, lemon juice, and capers to the same skillet, scraping up the browned bits for extra flavor. Let the sauce simmer for a few minutes.
Return the meatballs to the skillet and coat them in the sauce. Let everything simmer together until the meatballs are fully cooked and the sauce slightly thickens. Serve warm for the best flavor.