Traditionally, a gratin tends to be layered with cheese ... cover the dish tightly with foil. Bake the gratin for about 1 hour and 30 minutes, until the vegetables are tender.
It’s essentially a casserole. Typically there’s a hearty cream soup base, canned or frozen vegetables, lots of ground meat, and a crisp topping such as tater tots or crackers. It’s warm ...
Pour granola mixture onto your prepared pan, and spread it out in an even layer. Bake until lightly golden, about 24 minutes, stirring halfway. Remove from pan, and allow to cool completely.