Mince sun-dried tomatoes, basil, and parsley.

Melt butter in a large sauté pan or braiser. Add breadcrumbs and toast them until golden brown and fragrant. Remove from heat and set aside.

In a large mixing bowl, combine the toasted breadcrumbs, ground chicken, egg, garlic powder, oregano, basil, sun-dried tomatoes, salt, pepper, mayonnaise, and soy sauce. Mix gently using a fork or your hands until fully combined.

Heat vegetable oil in the same pan over medium heat. Using an ice cream scoop, scoop level portions of the meat mixture into the hot oil. Sear the meatballs until golden brown on at least two sides. Remove from the pan and set aside.

In the same pan, add butter and minced garlic. Cook for 2 minutes until fragrant, then add chili flakes.

Pour chicken broth into the pan and simmer for 3-4 minutes. Scrape any browned bits off the bottom of the pan to incorporate into the sauce.

Reduce heat to medium-low. Add room-temperature heavy cream, diced tomatoes, spinach, and Parmesan cheese. Stir well and bring to a simmer.

Return the browned meatballs to the pan and spoon the sauce over them as they finish cooking.

Continue cooking the meatballs until they reach an internal temperature of at least 165°F (around 15-20 more minutes).