In a glass measuring cup, combine egg yolks, lemon juice, salt and pepper. Blend with an immersion blender until pale yellow, about 30 seconds. Alternatively, use a blender.
With the blender running, slowly pour the hot butter into the yolks and blend until thick.
Preheat oven to 375°F.
Line a baking sheet with foil. Place halved English muffins bottom facing up and toast until crispy, about 5 minutes.
Flip English muffins and top each with a slice of Canadian bacon. Allow bacon to warm through, about 5 minutes.
Meanwhile, poach eggs and make hollandaise sauce.
To assemble benedict, place two slices of toasted English muffins and Canadian bacon on a plate. Top each muffin with a poached egg and drizzle with hollandaise sauce. Sprinkle top with chopped chives or parsley and serve.