Fill a medium saucepan with water and add the white vinegar, bringing it to a gentle simmer over medium heat.
In a small heat-proof bowl, whisk the egg yolk and lemon juice until slightly thickened, then slowly drizzle in the melted ghee while whisking constantly to create a smooth hollandaise.
Season the hollandaise with sea salt, black pepper, and a pinch of cayenne pepper, then keep warm by placing the bowl over a separate pot of warm water.
Heat a skillet over medium-high heat and sear the Canadian bacon slices for about 1-2 minutes per side until heated through and slightly browned.
Crack each egg into a small ramekin; use a spoon to create a gentle whirlpool in the simmering water and carefully drop the eggs in, poaching for 3 minutes for a runny yolk.
Split and toast the whole grain English muffin until golden brown, then place the halves on a plate.
Layer the Canadian bacon on each muffin half, top with a poached egg, and generously drizzle with the velvety hollandaise sauce.