Grease a 9x13 casserole dish with coconut oil or ghee.
Roughly tear apart the Udi’s Gluten Free Delicious Multigrain Sandwich Bread into 2-inch pieces and arrange in the pan in an even-ish layer. Pour the custard over the bread, using your hands or a spatula to press down any rogue pieces so they are all more or less submerged. Allow the bread to rest at room temperature for at least an hour so it absorbs the custard, or cover and place in the fridge to sit overnight.