In a large mixing bowl, combine ground turkey, ground chicken, grated cheese, minced garlic, Italian seasoning, bouillon cube, red chili flakes, chopped cilantro, and black pepper. Mix thoroughly but gently to keep the meatballs tender. Form into medium-sized meatballs and set aside on a plate.

Heat a large skillet over medium-low heat and add olive oil. Gently place the meatballs into the skillet, sear for 8-10 minutes, turning occasionally until browned and cooked through. Remove and set aside.

Melt butter in the same skillet, add minced garlic and sauté for 30 seconds, then add onion and cook until translucent. Incorporate sun-dried tomatoes and cook for 1-2 minutes.

Pour in vegetable broth and bring to a simmer, reduce for about 4-5 minutes. Stir in heavy cream, season with salt and pepper, and let simmer for another 3-4 minutes.

Fold in baby spinach into the sauce, cooking until wilted. Add grated Parmesan cheese and stir until melted and fully combined.

Return the seared meatballs to the skillet, spooning sauce over each. Simmer together for a couple of minutes before serving warm.