Combine basil leaves, ¼ cup Parmesan cheese, garlic, chicken/vegetable broth, salt, and pepper in a food processor or blender and process to a loose paste.
Set pesto sauce aside.
Bring a large pot of unsalted water to a boil and cook penne according to package directions. Drain and return to pot (cover to keep warm).
While pasta cooks, heat olive oil in a large skillet over medium heat.
Add the zucchini to the skillet and sauté until just softened, about 4 minutes.
Add tomatoes and continue to cook vegetables for another 2 to 3 minutes. Remove from heat.
Add sautéed vegetables and pesto sauce to pasta and gently toss until all ingredients are evenly coated with sauce. Top each serving with 2 tablespoons
Parmesan cheese, or simply toss remaining ½ cup Parmesan directly into pasta pesto and mix thoroughly before serving.