so far I have toasted a piece of Italian bread and a frozen waffle

I toast bread, English muffins, bagels and frozen waffles

I think that “Extra Wide Slot” can work for something like a waffle (stiff, with some bevel to the edges), but due to the design you'll have to first open the inner cage to insert many types of food to take advantage of the 1-3/8” maximum opening

Bread, frozen waffles, and