Cook macaroni in boiling water until tender.
Transfer macaroni to colander to drain and set aside.
Melt butter in pan and add flour.
Cook over low heat for about 2 minutes stirring constantly to make a roux.
Gradually add in a milk, whisking until smooth.
Cook for about 2 minutes, whisking constantly until you reach desired consistency.
Add in shredded cheddar cheese and stir until the melted and smooth.
Add drained macaroni to sauce and stir until coated.
Add salt and pepper to taste and serve.