01 -
Preheat the oven to 175°C and lightly grease a 23 x 33 cm casserole dish.
02 -
In a large mixing bowl, whisk together eggs, milk, Dijon mustard, garlic powder, onion powder, salt, and pepper until completely incorporated. Stir in shredded Swiss cheese and diced ham or Canadian bacon.
03 -
Distribute the toasted English muffin cubes evenly along the base of the prepared casserole dish. Pour the egg mixture over the muffin cubes, ensuring every piece is saturated. Press down gently to compact.
04 -
Cover the casserole tightly with aluminium foil. Bake for 30 minutes, then remove the foil and continue to bake for an additional 15–20 minutes until the centre is set and the top is golden brown.
05 -
During baking, melt unsalted butter in a small saucepan over low heat. In a separate bowl, whisk egg yolks with lemon juice until thickened and pale, about 2 minutes. Slowly drizzle in melted butter while whisking constantly to form a smooth, creamy sauce. Season with salt and cayenne pepper. Keep warm.
06 -
Allow the casserole to cool for several minutes. Cut into portions. Generously spoon warm Hollandaise sauce over each serving and sprinkle with chopped fresh chives before serving.