01 - Preheat your oven to 375°F (190°C). Grease a 9x13-inch baking dish.
02 - Spread the English muffin pieces evenly in the prepared baking dish. Top with the diced Canadian bacon.
03 - In a large bowl, whisk together eggs, milk, salt, and black pepper. Pour this mixture evenly over the muffin and bacon layer.
04 - Cover the dish with foil and refrigerate for at least 1 hour, or overnight for best results.
05 - Remove the casserole from the fridge while the oven preheats. Sprinkle paprika over the top.
06 - Bake, covered, for 30 minutes. Remove the foil and continue baking for 15–20 minutes, until the center is set and the top is lightly golden.
07 - While the casserole bakes, prepare the hollandaise: In a heatproof bowl over a pot of gently simmering water, whisk together egg yolks, lemon juice, salt, and cayenne for 2–3 minutes until slightly thickened. Slowly drizzle in the melted butter, whisking constantly, until the sauce is thick and glossy. Remove from heat.
08 - Let the casserole rest for 10 minutes before slicing. Serve slices topped generously with warm hollandaise sauce.