Grease a 2-quart baking dish with butter. In a large bowl, mix the vanilla wafers, apricots, raisins, sugar, salt, cinnamon, and nutmeg. Slice the bananas and fold into the dry ingredients. Transfer to the baking dish, distributing evenly. In another bowl, mix eggs, milk, vanilla and amaretto, whiskey or warm water.
Preheat oven to 350 degrees F. Pour the milk and egg mixture over the dry ingredients. Let the baking dish stand for about 20 minutes to allow the liquid to absorb.
Prepare a bain marie by placing the baking dish into a larger pan or dish, placing the arrangement into the preheated oven, and then pouring hot water into the outer dish (without splashing any into the custard dish). Bake until the pudding firms and puffs up and a toothpick inserted in the center comes out clean, about 1 hour. Remove from oven and from water bath. Spread apricot jelly over the top of pudding and let rest.
Increase oven heat to 425 degrees F.
To make the meringue topping, make a slurry with 1/3 cup water gradually whisked into a small saucepan to which you have added cornstarch and sugar. Bring to a boil over medium heat, whisking constantly. As it thickens and becomes translucent, cover and remove it from the heat. In a scrupulously clean large metal or glass bowl, with scrupulously clean beaters, beat the egg whites (they must be at room temperature) until foamy. Add vanilla and cream of tartar and beat until soft peaks form. Very gradually beat in sugar on high until glossy and stiff peaks form, but do not allow it to get dry. Reduce the speed of the beater to low and gradually add the cornstarch slurry. When it has all been added increase speed to medium for about 10 seconds.
Spread the meringue over the bread pudding, swirling it decoratively with the back of a spoon, and being sure to anchor the meringue to the sides of the baking dish. Bake until the meringue browns, 5 or 10 minutes.