Melt 1 1/2 Tbsp. butter in a medium skillet over medium-high heat. Sprinkle 2 Tbsp. flour into melted butter, whisking constantly. Cook, whisking constantly, 30 seconds to 1 minute or until mixture is golden and lumpy.
Gradually whisk in 1 cup 1% low-fat milk, and bring to a boil. Cook, whisking constantly, 1 to 2 minutes, or until thickened.
Add 1/2 cup freshly shredded Parmesan cheese, 1 tsp. hot sauce, 1/4 tsp. each salt and pepper, and a pinch of paprika, whisking until smooth. Remove from heat, and use immediately.