Bring a medium pot of salted water to a boil. Wash and dry produce.

Halve, peel, and finely dice onion. Core, deseed, and finely dice bell pepper. Trim and thinly slice scallions, separating whites from greens.

Pat chicken* dry with paper towels; season with 1 tsp Cajun Spice Blend (2 tsp for 4 servings), salt, and pepper.

Heat a drizzle of oil in a large pan over medium-high heat. Add chicken and cook until browned and cooked through, 5-6 minutes per side.

Turn off heat; transfer to a cutting board.

Once water is boiling, add linguine to pot. Cook, stirring occasionally, until al dente, 1-3 minutes. Reserve ¾ cup pasta cooking water (1¼ cups for 4 servings), then drain. 

Return same pot to stovetop over medium heat. Add a drizzle of olive oil, onion, bell pepper, salt, and pepper. Cook, stirring constantly, until tender, 3-4 minutes.

Add tomato paste and cook, stirring constantly, until fragrant, 30-60 seconds. Add reserved pasta cooking water, stock concentrate, cream cheese, garlic powder, remaining Cajun Spice Blend, and ½ tsp sugar (1 tsp for 4 servings); whisk to combine. Cook until slightly thickened, 30-60 seconds more.

Turn off heat. 

Stir 1 TBSP butter (2 TBSP for 4 servings) into pot with sauce until melted. Stir in drained linguine and scallion whites. Season with salt and pepper.

Thinly slice chicken crosswise.

Divide chicken and pasta between plates. Garnish with scallion greens and serve with hot sauce on the side.