Melt butter in medium-size saucepan. Whisk in flour; cook over medium heat about 1 minute. Slowly whisk in milk. Add salt, pepper, nutmeg and hot-pepper sauce; cook, whisking, 1 to 2 minutes or until mixture is very thick. Let cool; stir occasionally.
Heat oven to 350°F.
Process garlic, artichoke hearts and spinach in food processor until very smooth. Stir into cooled sauce. Reserve 3 tablespoons cheese. Stir remaining cheese into mixture. Spoon into 1-1/2 quart baking dish. Sprinkle with remaining cheese.
Bake in 350°F oven for 25 minutes or until heated.