Step 1: Fill a large pot with salted water and bring it to a boil. Add the rigatoni pasta and cook until al dente, about 10 to 12 minutes or according to package instructions. Drain the pasta well and set it aside.

Step 2: While the pasta is cooking, heat olive oil in a large skillet over medium-high heat. Add the chicken cubes and season with Cajun seasoning, salt, and pepper. Sauté the chicken for 6 to 8 minutes, stirring occasionally, until the pieces are golden brown and cooked through. Remove the chicken from the skillet and set aside.

Step 3: Reduce the heat to medium. In the same skillet, melt the butter. Add the minced garlic and sauté for about 1 minute, just until fragrant but not browned.

Step 4: Sprinkle in the flour and whisk constantly for 1 minute to create a roux. This will thicken your sauce and give it a lovely texture.

Step 5: Slowly pour in the whole milk while whisking continuously to prevent lumps. Bring the mixture to a gentle simmer and cook for 3 to 4 minutes until it thickens slightly.

Step 6: Lower the heat to low. Add the Velveeta cubes and cream cheese to the sauce. Stir gently until both cheeses are melted and the sauce becomes rich and creamy.

Step 7: Add the shredded mozzarella and Parmesan cheese. Stir until fully melted and the sauce is smooth and velvety. Taste and season with additional salt and pepper if needed.

Step 8: Return the cooked rigatoni pasta and chicken to the skillet. Gently toss everything together so the pasta and chicken are evenly coated in the sauce.

Step 9: Let the skillet sit over low heat for 2 to 3 minutes, allowing the flavors to meld and the sauce to thicken slightly.

Step 10: Garnish with freshly chopped parsley or basil if you like. Serve immediately while hot and creamy.