Dice chicken and season with seasonings. In a large skillet over medium heat, heat olive oil and cook chicken for a few minutes until done and set aside on a plate.
Cook rotini pasta according to package directions until al dente.
In the chicken skillet, melt butter and add in flour. Mix together and add white wine vinegar, garlic, onions, and Dijon mustard. Mix well for 3-5 minutes until onions are soft.
Slowly pour in milk and stir after each addition. Stir in cheddar cheese until melted. Add in chicken and red pepper flakes. Combine everything well and serve.