I heat the olive oil in a large pot over medium heat. Then I dice the onion, carrots, and celery, and add them to cook, stirring occasionally until they soften, about five to seven minutes. This builds the flavor base.
After those veggies are tender, I stir in the minced garlic and cook for another minute or two until fragrant. Then I pour in the crushed tomatoes and vegetable broth, mixing well. I bring it to a boil, then lower the heat to simmer so flavors meld, roughly 10 minutes.
Once the tomato mixture has simmered, I stir in heavy cream, dried basil, dried oregano, salt, and pepper, and let it warm back up gently. Then I drop in the cheese tortellini, cook according to package directions (usually about 5–7 minutes) until it’s tender. Finally, I taste and adjust the seasoning before serving.