Preheat your oven to 400°F. This ensures that your dish bakes evenly and turns golden brown. Get a 9×13-inch baking pan ready by spraying it with nonstick spray. This will help with easy cleanup later.
Next, heat olive oil and butter in a medium skillet over medium heat. Once the butter is melted, whisk in the flour, stirring until it’s lightly browned. This takes about a minute or so, and it’s important to keep stirring to avoid burning.
Gradually whisk in the evaporated milk, continuing to stir until the mixture thickens slightly. This step is crucial as it creates a creamy base for your sauce.
Now, it’s time to add the delicious cheeses. Whisk in the Monterey Jack cheese, Parmesan cheese, thyme, lemon zest, lemon juice, salt, and pepper. Keep whisking until everything is well combined and creamy.
While you’re making the sauce, the spaghetti should be cooking. Make sure to cook it until al dente according to package instructions. Drain and set aside.
In a large nonstick skillet, heat another teaspoon of olive oil over medium heat. Add the minced garlic and sauté for about one minute until fragrant. Be careful not to let it burn!
After that, toss in the broccoli, carrot, and bell pepper. Stir and cook for about 4 to 5 minutes until slightly softened. You want them to maintain some crunch and color.
Turn off the heat and add the cooked spaghetti to the skillet. Gently toss the spaghetti with the sautéed vegetables to mix everything together.
Add in the cooked and chopped chicken and pour the creamy sauce over the entire mixture. Toss until everything is evenly coated and well combined.
Transfer the pasta and vegetable mixture into the prepared baking pan. Spread the halved cherry tomatoes on top, sprinkling with more salt and pepper to taste.
Cover the baking pan with foil and bake for 30 minutes. Removing the foil after 30 minutes allows the top to brown nicely.
After 30 minutes, uncover the dish and sprinkle the remaining cheese on top. Squeeze the juice of ½ lemon over everything to brighten the flavors. Return it to the oven and bake until the cheese is melted and the tomatoes are wilted, about 10 more minutes.
Finally, scoop into dishes, serve hot, and enjoy every bite of your Baked Lemon Chicken Spaghetti Primavera!
