A casserole from pasta and vegetables in creamy, cheesy sauce!

Embark on a culinary journey with the Rainbow Garden Pasta Casserole!

This vibrant dish combines the wholesome goodness of broccoli and cauliflower with the delightful colors of tri-color rotini, all enveloped in a creamy, luscious sauce.

Rainbow Garden Pasta Casserole

Rainbow Garden Pasta Casserole

Perfect for family dinners or potluck gatherings, this casserole is sure to captivate your taste buds and add a splash of color to your dining table.

Skill Level: Beginner

This recipe is perfect for beginners. It involves simple cooking techniques like boiling pasta, steaming vegetables, and making a basic cream sauce.

There’s no complicated equipment or advanced skills required, making it a fun and easy dish for any home cook.

Health Benefits

  • Broccoli and Cauliflower: Rich in vitamins C and K, fiber, and antioxidants, these vegetables promote digestive health and may reduce inflammation.
  • Tri-color Rotini: Made with spinach and tomato, adding extra nutrients and flavors.

Time & Servings

  • Prep Time: 20 minutes
  • Cooking Time: 30 minutes
  • Total Time: 50 minutes
  • Servings: 6


  • Tri-color rotini pasta: 12 ounces (340 grams)
  • Fresh broccoli florets: 8 ounces (225 grams)
  • Fresh cauliflower florets: 8 ounces (225 grams)
  • Butter: 2 ounces (56 grams)
  • All-purpose flour: 1 ounce (28 grams)
  • Milk: 16 fluid ounces (473 milliliters)
  • Grated Parmesan cheese: 3 ounces (85 grams)
  • Shredded cheddar cheese: 4 ounces (113 grams)
  • Salt and pepper to taste

Optionally, you can use frozen broccoli and cauliflower florets for an ever easier dish.


  1. Preheat Oven: Set your oven to 350°F (175°C).
  2. Cook Pasta: Boil the rotini according to package instructions until al dente. Drain and set aside. (That’s about one minute under the cook time.)
  3. Steam Vegetables: Steam broccoli and cauliflower until tender-crisp, about 3-4 minutes. Set aside.
  4. Make Sauce: In a saucepan, melt butter over medium heat. Stir in flour to create a roux. Gradually add milk, whisking constantly to prevent lumps. Cook until the sauce thickens. Remove from heat, stir in Parmesan and half of the cheddar cheese until melted. Season with salt and pepper.
  5. Combine: In a large bowl, mix the cooked pasta, steamed vegetables, and cream sauce.
  6. Bake: Transfer the mixture to a greased baking dish. Sprinkle the top with the remaining cheddar cheese. Bake for 20-25 minutes or until the top is golden and bubbly.

Tips for Perfection

  • Al Dente Pasta: Cook the pasta just until al dente as it will continue to cook in the oven.
  • Cheese Quality: Use freshly grated cheese for a smoother, creamier sauce.
  • Vegetable Crunch: Don’t overcook the vegetables in the steamer; they should be tender but still crisp.

Optional Ingredients

  • Crunchy Topping: Add breadcrumbs mixed with melted butter on top for extra crunch.
  • Protein: Include cooked chicken or bacon for added protein.
  • Spice: Red pepper flakes for a bit of heat.

Steaming Veggies

Steaming vegetables is a simple and healthy cooking method that helps retain their nutrients, color, and texture.

Ways to steam veggies for your Rainbow Garden Pasta Casserole:

Traditional Steaming

  1. Using a Steamer Basket:
    • Fill a pot with about an inch or two of water. The water level should be just below the bottom of the steamer basket when it’s inserted.
    • Bring the water to a boil.
    • Place the chopped broccoli and cauliflower in the steamer basket. Ensure the vegetables are not submerged in water.
    • Cover the pot with a lid and let the vegetables steam until they are tender but still crisp, which usually takes about 3-4 minutes.
    • Once done, remove the vegetables immediately to stop the cooking process.

Alternative Methods

  1. Microwave Steaming:
    • Place the chopped vegetables in a microwave-safe steamer or bowl.
    • Add a small amount of water, just enough to cover the bottom of the bowl.
    • Cover the bowl with a microwave-safe lid or plate. Make sure there’s a small vent for steam to escape.
    • Microwave on high for about 2-3 minutes. Check for doneness and extend the time if needed, in 30-second increments.
  2. Steaming in a Pan:
    • Add a small amount of water to a pan (about ½ inch deep) and bring it to a simmer.
    • Add the vegetables, cover the pan with a lid, and let them steam for a few minutes.
  3. Electric Food Steamer:

Most Important Tips for Perfect Steaming

  • Don’t Overcrowd: Ensure there’s enough room in the steamer or pan so the steam can circulate around each piece.
  • Uniform Pieces: Cut the broccoli and cauliflower into similar-sized pieces for even cooking.
  • Check for Doneness: Vegetables should be vibrant in color and tender but still slightly crisp. Over-steaming can make them mushy and dull in color.
  • Immediate Removal: Once they’re done, remove them from the heat source to prevent overcooking.

By following these methods and tips, you can steam the vegetables perfectly for your casserole, retaining their nutritional value and delightful crunch.

Serving Suggestions

Serve this casserole hot, garnished with fresh parsley or basil. It pairs beautifully with a light salad and garlic bread.

Nutrient Information (Per Serving)

  • Calories: ~350
  • Protein: 15g
  • Carbohydrates: 45g
  • Fat: 15g
  • Fiber: 3g

Storing & Reheating

  • Storage: Cool completely and store in an airtight container in the refrigerator for up to 3 days.
  • Reheating: Reheat in the microwave or oven until heated through.

Origin and Folklore

The origins of pasta casseroles can be traced back to Italy, evolving from traditional baked pasta dishes.

Over time, they have become a staple in American cuisine, embodying the fusion of Italian and American cooking styles.


Rainbow Garden Pasta Casserole is not just a meal; it’s a celebration of colors, flavors, and textures.

Whether you’re a novice in the kitchen or looking to add some simplicity to your meal prep, this dish promises satisfaction and a delightful dining experience.

Enjoy your culinary creation!

You may also be interested in these other pasta dishes.

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