Grain-Free Swedish Meatballs in Gravy

Ingredients

• 1 pound ground beef ((grass-fed, if possible))
• 1 medium onion (finely diced)
• 1 tablespoon olive oil
• 2 large eggs
• 1/2 teaspoon nutmeg
• 1/4 teaspoon allspice
• 1/4 teaspoon pepper
• 1/8 teaspoon salt (or to taste)
• 1 cup chicken broth ((homemade, if possible))
• 1/2 tablespoon butter
• 1 tablespoon arrowroot starch