Preheat your oven to 325°F (160°C). Gather all your ingredients and let the cream cheese soften.

In a large mixing bowl, combine the imitation crab meat, half the mozzarella cheese, and half the Colby Jack cheese. Add in diced celery, sour cream, softened cream cheese, mayonnaise, Worcestershire sauce, lemon juice, white parts of green onions, and garlic salt. Stir until well combined.

Transfer the mixture to a greased casserole dish and spread it evenly across the bottom.

Sprinkle the remaining mozzarella and Colby Jack cheeses generously over the top of the mixture.

Place the casserole in the oven and bake for about 20 minutes, until the cheese is bubbly and golden brown.

Allow to cool slightly before serving. Sprinkle the green portions of the sliced green onions on top just before serving.