Meanwhile, in 2-quart saucepan, melt butter over medium heat. Add shallot and garlic; cook and stir 1 minute. In medium bowl, beat half-and-half and flour with wire whisk; add to saucepan. Heat to boiling, stirring frequently. Beat in sour cream with wire whisk. Reduce heat to low; cook 1 to 2 minutes or until heated. Remove from heat; stir in 1/4 cup cheese, the salt and pepper.