Preheat your oven to 400°F (200°C).

On a large baking sheet, combine the zucchini, red bell pepper, yellow bell pepper, red onion, and cherry tomatoes. Drizzle with 2 tbsp of olive oil and sprinkle with dried oregano, 1/2 tsp salt, and 1/4 tsp black pepper. Toss well to coat.

Roast for 20-25 minutes, stirring halfway through, until the vegetables are tender and lightly caramelized at the edges.

While the vegetables are roasting, bring a large pot of salted water to a boil. Cook the penne pasta according to package directions until al dente. Drain and set aside, reserving about 1/2 cup of the pasta water.

In a large skillet or pot, heat 1 tbsp of olive oil over medium heat. Add the minced garlic and cook for about 1 minute until fragrant, being careful not to burn it.

Stir in the crushed tomatoes, vegetable broth, dried basil, and optional red pepper flakes. Bring to a simmer and cook for 5-7 minutes, allowing the flavors to meld. Season with salt and pepper to taste.

In a large mixing bowl, combine the drained pasta, the roasted vegetables, and the tomato sauce. Gently stir in the halved Kalamata olives and about half of the crumbled feta cheese. If the mixture seems too thick, add a splash of the reserved pasta water.

Transfer the pasta mixture to a 9x13-inch baking dish and spread it into an even layer.

Sprinkle the shredded mozzarella cheese evenly over the top, followed by the remaining crumbled feta cheese.

Bake, uncovered, for 15-20 minutes, or until the cheese is melted, bubbly, and lightly golden on top.

Let the pasta bake rest for 5-10 minutes before serving. Garnish with fresh chopped parsley.