Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.
In a mixing bowl, combine the shredded mozzarella, cream cheese, chopped spinach, Parmesan cheese, garlic powder, onion powder, salt, black pepper, and crushed red pepper flakes (if using). Mix until well combined.
Using a tablespoon, scoop the cheese mixture onto the prepared baking sheet, spacing them about 2 inches apart. Flatten each scoop slightly with the back of the spoon.
Bake in the preheated oven for 12-15 minutes, or until the edges are golden and the cheese is bubbly.
Remove from the oven and let cool for a few minutes before transferring to a serving platter.
Garnish with chopped green onions before serving.