Summarize the following:
The sauce should be bubbling and the top will become crispy and golden brown once the casserole has finished baking. Serve the casserole with green beans, steamed vegetables, or a tossed salad. Refrigerate leftovers in an airtight container for up to 3 or 4 days.

Summary:
Bake the tuna casserole for 45 to 50 minutes.