To prepare pasta:
Place 5 cups of water in a big soup pot. Pour 2 tbsp salt into water. Bring water to a boil. Cook macaroni until noodles are al dente. Remove from heat and strain. Stir noodles with olive oil to keep the macaroni from sticking together.
Grease a large baking dish. Pour macaroni into baking dish and set aside.
To prepare cheese sauce:
In a large saucepan, melt butter over medium heat. Add flour, 1 tsp salt, pepper, and paprika. Stir until mixture starts to bubble up to form a roux.
Next, add milk and cream cheese. Stir until cream cheese has melted and sauce has thickened. Slowly add cheddar cheese until everything is melted. Season sauce with old bay. Remove from heat. Mix in king crab meat.
Tip: Using fresh shredding block cheese creates a better texture/flavor!
Preheat oven to 350. Mix parmesan cheese and breadcrumbs together in a small bowl. Pour cheese sauce into large baking dish, over top of the cooked macaroni. Top with cheesy breadcrumbs. Cook in oven for 30 minutes until the top is golden brown.