Step 1

For the casserole: Grease a 9-by-13-inch baking dish with the butter.

Step 2

Split the English muffins open. Shingle the English muffins split-sides up in the baking dish in 2 rows, alternating tops and bottoms. Place 1 slice of Canadian bacon in between each piece.

Step 3

Whisk together the milk, cream, nutmeg, salt, pepper and eggs in a medium bowl until well combined. Pour the custard over the top of the English muffins, then cover the baking dish with plastic wrap and refrigerate 8 hours or up to overnight. (See Cook's Note.)

Step 4

Preheat the oven to 350 degrees F.

Step 5

Remove the plastic wrap from the casserole dish and replace with foil. Bake 30 minutes, then remove the foil and bake until the casserole is set and the English muffins and bacon have browned on the edges, an additional 30 minutes.

Step 6

For the hollandaise sauce: Meanwhile, melt the butter in a medium saucepan over medium heat. Add the yolks, lemon juice, salt and cayenne to a blender and blend for 1 minute. With the blender running, pour the melted butter very slowly through the open hole of the blender lid.

Step 7

For the poached eggs: Fill a large saucepan with 2 quarts water. Add the vinegar and bring to a steady simmer over medium-high heat.

Step 8

Crack 4 eggs into small cups or glasses. (If your simmering water has reduced too much, add a bit more water and bring back to a steady simmer.) Slip the eggs into the water in one quick motion. Poach the eggs until the whites are firm but the yolks are still runny, 4 to 5 minutes. Remove the eggs with a slotted spoon and drain on a paper towel. Repeat with 4 more eggs.

Step 9

Arrange 4 eggs on each side of the baked casserole. Drizzle the hollandaise sauce over the top and sprinkle with the chives. Serve while still warm with extra hollandaise sauce on the side. (If the sauce has thickened too much, whisk it with a tablespoon of water.)