01 - Melt butter in a medium saucepan over medium heat. Add flour and whisk constantly for 1 minute to form a roux, taking care not to let it brown.
02 - Gradually whisk in milk, stirring frequently until mixture thickens and reaches a simmer, approximately 2-3 minutes.
03 - Reduce heat to low. Incorporate Dijon mustard, hot sauce, garlic powder, cayenne pepper, salt, and black pepper. Stir until well combined.
04 - Add grated cheddar cheese gradually, whisking after each addition until smooth and fully melted before adding more.
05 - Once all cheese is incorporated and sauce is smooth, taste and adjust seasoning as desired. Serve immediately while hot.