In a large mixing bowl, combine the ground chicken, canned pumpkin purée, plain breadcrumbs, egg, grated garlic, onion powder, salt, and pepper. Gently mix the ingredients using your hands until just combined.

Using your hands, scoop out portions of the mixture and roll them into 1.5-inch meatballs. Place the formed meatballs on a plate while preheating your skillet over medium heat.

In a nonstick skillet, heat a drizzle of olive oil over medium heat. Carefully add the meatballs to the skillet in batches and cook for 2-3 minutes on each side, until golden brown and cooked through, about 10-12 minutes total.

In a separate saucepan, melt unsalted butter over medium heat. Once melted, add the grated garlic and chopped fresh sage, sautéing for about 30 seconds until fragrant.

Pour in the heavy cream, whisking to combine with the garlic and sage mixture. Season the sauce with additional salt, pepper, and a pinch of nutmeg. Let the sauce simmer gently for 3-4 minutes.

Add the browned pumpkin chicken meatballs into the creamy sage sauce, allowing them to simmer together for an additional 5-7 minutes.

Once cooked, plate the meatballs and cream sauce, sprinkling extra chopped sage and cracked black pepper on top. Serve over pasta, rice, or alongside a green salad.