Bring a large pot of salted water to a boil. Add your whole wheat linguine noodles or pasta of choice. Cook according to package instructions until al dente. Drain and set aside, reserving a small cup of pasta water for later use.
In a medium bowl, toss the peeled and deveined shrimp with 1 teaspoon of Cajun seasoning, ½ teaspoon of garlic powder, ½ teaspoon of kosher salt, and ½ teaspoon of black pepper. Make sure each shrimp is well-coated.
In a large skillet, heat the extra-virgin olive oil and 1 tablespoon of butter over medium heat. Add the sliced bell peppers, mushrooms, and half of the green onions. Sauté for about 5-7 minutes until the vegetables are tender and slightly caramelized.
Push the sautéed vegetables to the side of the skillet and add the seasoned shrimp. Cook for about 2-3 minutes on each side until the shrimp turn pink and opaque.
In a small bowl, whisk together the nonfat milk and cornstarch until smooth. Pour this mixture into the skillet with the shrimp and vegetables. Stir in the fire-roasted diced tomatoes, remaining Cajun seasoning, garlic powder, kosher salt, and black pepper.
Add the softened light cream cheese to the skillet, stirring until it melts and combines with the sauce, creating a creamy texture. If the sauce is too thick, add a splash of the reserved pasta water to reach your desired consistency.
Add the cooked linguine to the skillet, tossing everything together until the pasta is well coated with the creamy Cajun sauce. Adjust seasoning with salt and pepper to taste.
Serve the Cajun Shrimp Pasta in bowls, garnished with the remaining sliced green onions for a fresh touch. Enjoy your delicious, homemade meal!