Add the ground meat to a large mixing bowl along with the almond flour, egg, and seasonings. Using clean hands or a spoon, gently mix everything together just until combined. Be careful not to overwork the mixture — stopping as soon as it comes together helps keep the meatballs tender and juicy instead of dense.

Scoop out portions of the mixture and roll them between your palms to form evenly sized meatballs. Keeping them uniform in size ensures they brown evenly and finish cooking at the same time later in the oven.

Heat a skillet over medium heat and add a small amount of oil or butter. Place the meatballs in the skillet with space between them and brown on all sides, turning gently as they cook. At this stage, you’re only developing color and flavor, not cooking them all the way through. Once browned, transfer the meatballs to a plate and set aside.

In the same skillet, reduce the heat slightly and add the butter. Let it melt slowly, scraping up any browned bits left behind from the meatballs — these add a lot of flavor to the sauce. Pour in the broth and stir, allowing it to simmer gently for a minute so the flavors begin to blend.

Slowly add the cream to the skillet, stirring continuously to create a smooth base. Stir in the mustard, Worcestershire sauce, and additional seasoning. Let the sauce simmer gently until it starts to thicken slightly, keeping the heat low to prevent separation.

Return the browned meatballs to the skillet and gently stir so they are fully coated in the creamy sauce. Let them simmer together briefly, allowing the meatballs to absorb flavor while finishing their cooking gently in the sauce.

Transfer the meatballs and sauce into a lightly greased baking dish, spreading everything out evenly so the meatballs are well surrounded by sauce. Place the dish in the oven and bake until the sauce is bubbling gently and the meatballs are fully cooked through. Allow the casserole to rest for a few minutes before serving so the sauce can settle and thicken slightly.