Preheat oven to 350°F. Generously grease a 2-quart casserole. 

For ginger garlic paste: Ginger garlic paste provides the background flavor of many South Indian dishes. It can be purchased at Indian grocery stores or made at home by using one-third fresh garlic to two-thirds fresh ginger by weight. Process in a food processor, using as little water as necessary to make a paste. Refrigerated, it will keep for at least a week. 

For topping: In a bowl, combine bread crumbs, Asiago, and paprika. Set aside. 

Cook macaroni al dente, according to package directions. Drain and put into prepared casserole. 

For sauce: In another bowl, combine garam masala, salt, pepper, turmeric, and cayenne. Set aside.

Melt butter in a saucepan over medium heat. Add ginger garlic paste as butter is melting. (If added to hot butter, paste will spatter wildly; heat slowly in melting butter.) Add spice mixture and cook for 2 to 3 minutes, stirring constantly. Add flour and cook for 1 to 2 minutes over medium heat. Add milk slowly, stirring constantly until mixture boils for at least 1 minute, or until incorporated. Remove from heat and fold in shredded cheese. 

To assemble: Pour sauce over cooked macaroni and stir gently to combine. Sprinkle with bread crumbs mixture. Bake for 25 to 30 minutes, or until bubbly. 

Makes 6 to 8 servings.