Cut the bread into cubes and place in a bowl. Pour over the milk, then add enough water (or more milk if you're feeling rich) to cover.
Let the cubes soak in the milk until they are soft, about 30 minutes.Place the soaked bread cubes in a colander to drain.
Beat the eggs with the cheese and parsley, seasoning generously with salt and pepper. Squeeze the bread cubes of their liquid and add them to the bowl. Give it all a turn to mix everything well. Let rest for a few minutes to let the egg mixtures impregnate the bread.
Heat some olive oil in a non-stick or carbon steel skillet, add the eggs and proceed to fry one side, then the other, over gentle heat, following our instructions for making a frittata. The frittata should be thoroughly cooked through and nicely browned on both sides. You can test the frittata for doneness by piercing it with a paring knife; if it comes out clean, the frittata should be done.
Turn out the frittata on to a serving plate and let it cool a bit before serving. Bread Frittata is also quite nice at room temperature.