Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper and lightly grease it with cooking spray or olive oil.

In a large pot of boiling water, blanch the chopped broccoli for about 2 minutes until bright green and slightly tender. Drain and immediately transfer to a bowl of ice water to stop the cooking process. Once cooled, drain again and chop finely.

In a mixing bowl, combine the blanched broccoli, cheddar cheese, breadcrumbs, Parmesan cheese, eggs, green onions, garlic powder, onion powder, salt, black pepper, and red pepper flakes (if using). Mix until well combined.

Using your hands or a spoon, form the mixture into small patties, about 2-3 inches in diameter, and place them on the prepared baking sheet.

Bake in the preheated oven for 20-25 minutes, flipping halfway through, until the fritters are golden brown and crispy on the outside.

Remove from the oven and let cool for a few minutes before serving.