Make the Meatballs:

• In a large mixing bowl, combine the ground beef, grated onion, almond flour, egg, salt, pepper, garlic powder, and allspice. Mix well until thoroughly combined. Roll the mixture into 20 small meatballs.
  
• In a large skillet, heat the olive oil over medium-high heat. Add the meatballs and cook, turning every few minutes, until browned on each side and no longer pink inside, about 7-10 minutes. You may need to cook in two batches to avoid overcrowding the skillet. Transfer the meatballs to a plate while you make the sauce.
• In the same skillet, still over medium-high heat, whisk together the broth and heavy cream. Scrape up any browned bits from the skillet for extra flavor. Add the Dijon mustard and soy sauce sauce. Bring the mixture to a gentle simmer, not a full boil. Let it simmer, stirring occasionally, until the sauce has thickened enough to coat the back of a spoon, about 6-8 minutes.
  
• Season to taste with salt and pepper. Add the meatballs back to the skillet to warm for another 1-2 minutes, or pour the hot sauce over the meatballs. Serve immediately.