Heat the oil in a large skillet, add garlic and cook on medium–high heat for 2 minutes until fragrant. Add cubed peppers and rosemary, season with salt, pepper, and sauté for 4 minutes. Add olives and continue cooking for two more minutes until peppers cooked through but still al dente.
In the meantime, cook the Tortellini in a large saucepan of salted boiling water according to package instructions and drain, reserving 1/2 cup (120 ml) of the cooking water.
Add the Tortellini to the skillet with reserved liquid and toss to combine. Divide among plates, drizzle with extra oil and serve.