Boil water in a large pot; add salt and cook the cheese tortellini according to package instructions until they float. Drain and rinse under cold water.

While the tortellini cools, chop cherry tomatoes, red onion, basil leaves, and thawed green peas.

In a large mixing bowl, combine cooled tortellini with chopped veggies. Drizzle with olive oil and balsamic vinegar; season with salt and pepper.

Toss gently until everything is coated. Let rest for 10 minutes at room temperature or chill before serving.