Heat olive oil in a skillet over medium heat.
Add diced onion and cook until softened.
Stir in minced garlic and sauté briefly.
Transfer the sautéed mixture to the slow cooker.
Add chopped leftover turkey into the pot.
Spoon in canned pumpkin evenly.
Pour chicken broth over the ingredients.
Sprinkle cinnamon and ground ginger into the mixture.
Season lightly with salt and pepper.
Stir gently until well combined.
Cook on low for 4–5 hours or just until heated through and flavors are blended, since the turkey is already cooked.
Taste, adjust seasoning, and serve hot.