Bring a large pot of salted water to a rolling boil. Cook the penne pasta according to package instructions until al dente, around 8-10 minutes, reserving ½ cup of pasta water before draining.

In a deep skillet, heat 2 tablespoons of olive oil over medium-high heat. Add chopped red onion and carrot, sauté for 2 minutes until softened and translucent.

Incorporate broccoli florets and diced bell pepper into the skillet, sauté for an additional 2 minutes until broccoli is bright green.

Add sliced zucchini and yellow squash, cooking for about 3 minutes until tender yet slightly crunchy.

Stir in minced garlic and chopped tomatoes along with Italian seasoning, sauté for another 2 minutes until fragrant.

Transfer sautéed vegetables to a large mixing bowl. Add in the drained penne pasta and toss together, adding more olive oil if desired.

Squeeze fresh lemon juice over the mixture, season with salt and pepper. Gradually add reserved pasta water to achieve desired sauce consistency.

Toss with freshly grated Parmesan cheese and chopped parsley before serving immediately.