Preheat the oven to 400°F and line a baking sheet with parchment paper.
In a large bowl add: 1 pound lean ground beef, ½ cup gluten-free breadcrumbs, ¼ cup grated Parmesan cheese, 1 large egg, 2 tablespoons fresh parsley (finely chopped), 1 teaspoon garlic powder, 1 teaspoon onion powder, ½ teaspoon salt, ¼ teaspoon black pepper, and ¼ teaspoon dried oregano.
Gently mix the ingredients with clean hands or a spoon until just combined—do not overwork the meat.
Form the mixture into 1½-inch meatballs by scooping or pinching portions and rolling them between your palms. Place the meatballs on the prepared baking sheet, spaced evenly apart.
Bake in the preheated oven for 20–25 minutes, or until an instant-read thermometer inserted into the center of a meatball registers 165°F.
Remove from the oven and let the meatballs sit briefly before serving.