In a large mixing bowl, combine lean ground turkey, apple cider, whole wheat breadcrumbs, egg, finely diced onion, minced garlic, cinnamon, nutmeg, and allspice. Mix gently until just combined and let sit for about 10 minutes.

With wet hands, scoop portions of the mixture and roll into 1 to 1.5-inch meatballs. Place on a parchment-lined baking sheet and chill in the refrigerator for 15-20 minutes.

Heat a skillet over medium heat with a tablespoon of olive oil. Sear the meatballs for about 4-5 minutes on each side until golden brown and cooked to an internal temperature of 165°F.

In the same skillet, reduce heat to low and add apple cider, maple syrup, and Dijon mustard. Simmer for about 3-4 minutes until slightly thickened.

Return cooked meatballs to the skillet and gently coat them in the glaze for an additional minute or two before serving hot.