Fill a medium saucepan with water and add the white vinegar; bring to a gentle simmer over medium heat.
In a small heat-proof glass bowl, whisk the single egg yolk and lemon juice together until the mixture slightly thickens.
Place the bowl over the pot of simmering water to create a double boiler, and very slowly drizzle in the melted ghee while whisking constantly until the sauce is thick and creamy.
Stir the sea salt and cayenne pepper into the hollandaise sauce, then remove from heat and cover to keep warm.
In a small skillet over medium heat, lightly sear the Canadian bacon slices for 1-2 minutes per side until warmed through.
Crack the remaining 2 eggs into individual small ramekins; use a spoon to create a gentle whirlpool in the simmering water and slide the eggs in.
Poach the eggs for approximately 3 minutes until the whites are fully set but the yolks remain soft and runny.
Split and toast the English muffin until the edges are golden and crisp.
To assemble, place two slices of Canadian bacon on each muffin half, top with a poached egg, and drizzle with the warm hollandaise sauce and black pepper.