I've tried this recipe with a whole egg and it comes out much moister, but the taste is a bit more flavorful thanks to the yolk. The texture is slightly different as well; a bit spongier. If you want to purchase a container of egg whites instead of using a whole egg and having a leftover yolk, 1 large egg white is equal to 2 tablespoons of egg white.I managed to get 4 thin slices from this recipe, but most of the time you'll get 2 thick slices, or 3 thinner slices.I used a 3.5 inch ( 8.9 cm) ramekin (in diameter), which holds about 4 ounces of liquid. A slightly larger diameter would have yielded closer to 2 slices.If you don't have a microwave or don't use one, you can bake it but it does crumble a bit. To bake it, generously oil the inside of the ramekin or bowl, and bake in a preheated oven or toaster oven at 400° F (200° C, or gas mark 6) for 15 minutes, or until it's solid. You may need to slide a knife along the sides to wiggle the muffin out of the ramekin.