Bring a large pot of salted water to a rolling boil over high heat. Add penne pasta and cook for 10-12 minutes, or until al dente. Reserve ½ cup of the starchy pasta water, then drain the rest.

In a deep skillet or large sauté pan, heat 2 tablespoons of olive oil over medium-high heat. Allow the oil to shimmer.

Add diced red onion and sliced carrots to the skillet, sautéing for about 2 minutes until fragrant and the onions have slightly softened.

Toss in the broccoli florets and sliced red bell pepper into the skillet. Sauté for another 2 minutes, allowing the vegetables to turn bright and tender-crisp.

Stir in the yellow squash and zucchini, continuing to sauté for an additional 2-3 minutes until just starting to soften.

Add minced garlic, halved grape tomatoes, and dried Italian seasoning to the skillet. Sauté for another 2 minutes.

Carefully add the drained penne pasta to the skillet, mixing well with the sautéed vegetables.

Drizzle fresh lemon juice over the pasta mixture and season with salt to taste. Add reserved pasta water to reach desired consistency.

Sprinkle grated Parmesan cheese and chopped fresh parsley over the dish, tossing lightly to combine.