Bring a large pot of salted water to a boil and cook the potato gnocchi according to package directions until they float and are tender; drain in a colander.
While the gnocchi cooks, heat the olive oil in a large skillet over medium heat.
Add the diced zucchini and chopped yellow pepper to the skillet and saute until tender, about 4–6 minutes.
Reduce heat to low, stir the pesto into the skillet, then add the drained gnocchi and gently toss to coat evenly with the sauce.
Stir in the chopped tomatoes just until warmed through, being careful not to break them apart.
Serve topped with toasted pine nuts and shredded Parmesan cheese if using.
