Bring a large pot of water to a boil and cook the ravioli according to package directions.
Once cooked, drain well and return the ravioli to the warm pot to keep it from getting cold.
While the ravioli is cooking, heat the olive oil in a large skillet over medium heat.
Add the halved tomatoes and sliced mushrooms, cooking for 5 to 7 minutes.
Stir occasionally until the mushrooms are tender and the tomatoes have softened and started to release their juices.
Add the basil pesto to the pot with the drained ravioli and toss gently to coat each piece evenly. Carefully fold in the cooked tomato and mushroom mixture, along with the fresh shredded basil.
Serve immediately.
Reserve about 1/4 cup (960 ml) of the starchy pasta water before draining the ravioli. You can add a splash to the final dish if your pesto sauce seems too thick.
