Step 1

In a heavy saucepan, melt the butter over medium heat, add the flour and stir until combined and lightly browned. Add the onion and celery to the mixture and cook on low-medium heat until the vegetables are tender.

Step 2

Add the evaporated milk, egg yolk, cheese, salt, black pepper and cayenne pepper, and stir continuously until the cheese has melted.

Step 3

Gently stir in the crab meat and cook on low heat for 5 minutes to heat through. Turn oven broiler on to HIGH. Scoop the mixture into a small oven-safe baking dish and top with reserved Swiss cheese, green onion and paprika.

Step 4

Place the baking dish onto a cookie sheet and place under broiler for 5 minutes, or until the cheese has melted and started to turn brown and bubbly. Remove from oven and serve warm with crackers.