Preheat oven to 425°F. Line a large baking sheet with foil and spray lightly with oil.
In a large bowl, combine the ground chicken, egg, ½ cup cheese, breadcrumbs, oil, parsley, garlic powder, salt, and pepper. Mix well.
1 pound ground chicken, 1 large egg, 2 cups freshly grated Gruyere cheese, ⅓ cup Panko breadcrumbs, 1 tablespoon olive oil, 1 tablespoon chopped fresh parsley, ½ teaspoon garlic powder, ½ teaspoon kosher salt, ¼ teaspoon ground black pepper
Roll the meat into 16 meatballs and place them in a single layer on the baking sheet.
Bake for 25-30 minutes, until golden and cooked through.
While the meatballs are baking, melt the butter with the onions in a Dutch oven set over medium heat.
¼ cup unsalted butter, 2 yellow onions
Cover and cook, stirring occasionally until softened, about 10 minutes.
Remove the lid and slowly add the wine, ¼ cup at a time, until it evaporates as it cooks into the onions.
½ cup dry white wine
Once all the wine has been added, reduce the heat to medium-low, cover, and continue to cook for another 10-15 minutes, stirring often, until the onions are soft and caramelized.
Add the garlic and thyme, season with salt and pepper, and cook for 1-2 minutes until fragrant. Add the broth and bring the mixture to a low boil.
Add the cooked meatballs to the skillet and simmer for 8-10 minutes, spooning the broth over them occasionally, until it has reduced by about half.
Meanwhile, arrange the slices of bread on a baking sheet and toast for 10 minutes, until dry. Remove from the oven and turn the oven to broil.
1 loaf french bread
Place the bread slices between the meatballs in the skillet and sprinkle the top evenly with cheese. Broil until bubbly and golden brown, 3-5 minutes. Serve warm, garnished with thyme.
Notes
A serving is 2 meatballs and 2 slices of bread.
Use cold ingredients straight from the refrigerator. This will make the meatballs easier to roll.
You can use beef or turkey instead of chicken.
To make these meatballs keto-friendly, swap the breadcrumbs for almond meal.
To make these meatballs gluten-free, swap the breadcrumbs for gluten-free breadcrumbs.
I recommend using freshly-shredded cheese, as it melts better than pre-shredded.
If you find that your meatballs are not sticking together after adding the breadcrumbs and eggs, you may need to add some liquid (I like to use about 2 tablespoons of milk) to help them stick together.
Make sure to fold the meatball mixture together gently so as not to overwork the meat.
Gently roll the meatballs into balls. Don’t over-compact them, or they could turn out tough.
Chicken meatballs are fully cooked when they reach 165°F internally.
Storage: Store French onion chicken meatballs in an airtight container in the refrigerator for up to 3 days or in the freezer for up to 2 months.