Bring a large pot of salted water to a boil over high heat. Add the whole wheat linguine noodles and cook according to package instructions until al dente, approximately 8–10 minutes. Drain and set aside.

In a large skillet, heat 2 tablespoons of extra-virgin olive oil over medium-high heat. Season the shrimp with Cajun seasoning, garlic powder, salt, and pepper. Cook for 3–5 minutes until pink and firm, then remove from the skillet and keep warm.

Lower heat to medium and add 2 tablespoons of unsalted butter. Sauté diced bell peppers for about 3 minutes, then add cremini mushrooms and an additional pinch of salt. Cook for about 5 minutes until tender, then add fire-roasted diced tomatoes and cook for another 3 minutes.

Stir in two-thirds of the chopped green onions and add cooked shrimp back into the skillet to combine flavors.

Whisk together 1 cup of nonfat milk and 1 tablespoon of cornstarch until smooth. Pour into the skillet with remaining butter and simmer for 2–3 minutes. Add light cream cheese and whisk until the sauce thickens.

Return drained pasta to the skillet, tossing everything to coat the linguine. Cook for an additional 1–2 minutes, adjusting seasoning as necessary.

Garnish with remaining chopped green onions and serve immediately.