Cut the bread into ½-inch cubes and toss the cubes with melted butter. Spread the buttered cubes out on a baking sheet and toast the bread in the oven for 10 minutes.

Combine four eggs and the half-and-half in a large bowl, whisk together and season with salt and freshly ground black pepper. Add the toasted bread cubes, diced Canadian bacon and tarragon to the bowl and toss to coat the bread. Let the mixture rest for 20 minutes so the bread has time to absorb the egg custard (and you have time to prepare the Hollandaise Sauce).

Spoon the mixture into the buttered ramekins. Make a 2-inch well in the center of the mixture with the back of a spoon. Cover the ramekins with foil and place them on a baking sheet. Bake at 350°F for 25 minutes.

Remove the baking sheet from the oven and remove the aluminum foil from the ramekins. Crack one of the remaining eggs into the well of each ramekin. Return the ramekins to the oven uncovered and bake for an additional 12 to 15 minutes, until the egg has set but the yolk is not firm. Garnish with fresh tarragon leaves. Serve immediately with the Hollandaise Sauce.