Preheat oven to 400 degrees Fahrenheit (200 degrees Celsius).
On a large rimmed sheet pan, combine refrigerated tortellini, broccoli florets, and halved cherry tomatoes.
Drizzle olive oil over the ingredients and sprinkle with minced garlic, Italian seasoning, salt, and black pepper.
Toss the ingredients thoroughly on the pan to ensure an even coating of oil and spices.
Spread the mixture into a single, even layer to ensure uniform cooking.
Bake in the preheated oven for 15 to 18 minutes until the broccoli is tender-crisp and tortellini edges are slightly toasted.
Remove the pan from the oven and sprinkle evenly with shredded mozzarella and grated Parmesan cheese.
Return the pan to the oven for 2 to 3 minutes until the cheese is melted and bubbling.
Remove from oven and garnish with red pepper flakes before serving.