Season the boneless, skinless chicken breasts with salt and pepper, then cook in a skillet with olive oil over medium heat for 6-7 minutes on each side until fully cooked. Shred the chicken.

Bring a large pot of salted water to a rolling boil, add macaroni, and cook according to package instructions (about 7-8 minutes) until al dente. Drain and set aside.

In a medium saucepan, melt butter over medium heat and whisk in the flour. Gradually pour in milk while continuously whisking. Simmer for 3-4 minutes until thickened, then stir in garlic powder and onion powder.

Remove the sauce from heat and add both cheeses, stirring until melted and smooth. Adjust seasoning with salt and pepper.

Combine shredded chicken and pasta in a large mixing bowl, then pour the cheese sauce and BBQ sauce over, stirring to coat evenly.

Serve hot, garnished with herbs or additional BBQ sauce as desired.