Spray the inside of crockpot with a cooking spray.
Cook pasta per instruction until al dente. Drain and mix 1 TBS butter in pasta.
Place pasta into crockpot. Place 3/4 cup of each of the 3 cheeses on top. Add butter, evaporated milk, half & half, salt, pepper, onion powder, and paprika. Mix together well.
Place lid on crockpot and cook on low for 1 1/2 hours to 2 hours. Stir every 1/2 hour. On the last 1/2 hour, add rest of the cheeses on top and cover for 30 minutes. Enjoy.
