Preheat oven to 350°F and grease a 9x13-inch baking dish.
Cook elbow macaroni according to package directions until al dente, drain and set aside.
In a large saucepan, melt butter over medium heat, then whisk in flour and cook for 1-2 minutes until golden.
Gradually whisk in milk and cook, stirring constantly, until mixture thickens and comes to a gentle simmer, about 5-7 minutes.
Remove from heat and stir in cheddar and Colby cheeses until completely melted and smooth.
Add salt, pepper, and paprika, then fold in cooked macaroni until evenly coated.
Pour mixture into prepared baking dish and bake for 20-25 minutes until bubbly and golden on top.
Let stand 5 minutes before serving.