Toast the English muffins until the cut sides are lightly crisp.
Brown the Canadian bacon in a skillet over medium heat for 1 minute per side, then transfer it to a plate.
Melt the butter in the skillet and set four greased egg rings in place.
Crack one egg into each ring, pierce the yolks, season with salt and black pepper, and cover for 3 to 4 minutes until 160°F.
Top each egg with one American cheese slice and cover for 30 seconds.
Fill each muffin with two Canadian-bacon slices and one cheesy egg.