To make the hollandaise sauce, whisk the egg yolks, lemon juice, cayenne pepper, and salt in a heatproof bowl set over a saucepan of simmering water. Gradually whisk in the melted butter until the sauce is thick and smooth. Remove from heat and keep warm.
Toast the English muffin halves until golden brown.
Heat a skillet over medium heat and cook the Canadian bacon slices until heated through and lightly browned.
Poach the eggs: Fill a large skillet with about 2 inches of water, add the white vinegar, and bring to a gentle simmer. Crack each egg into a small bowl, then carefully slip them into the simmering water. Poach for 3-4 minutes, or until the whites are set and the yolks are still runny.
Assemble the Eggs Benedict: Place a toasted English muffin half on each plate. Top with a slice of Canadian bacon, then a poached egg. Spoon a generous amount of hollandaise sauce over the egg. Garnish with chopped chives, if desired.
Notes
For best results, ensure all ingredients for the hollandaise are at room temperature. Serve immediately.