Melt the unsalted butter in a small saucepan over low heat until fully melted. Skim foam and carefully pour off clear butter into a heatproof bowl, leaving milky solids behind (about 100–110 g of clear butter). Keep warm but not hot (set bowl over barely-warm water).

Make the emulsion

In a medium heatproof bowl (or the top of a double boiler), whisk together the egg yolks, lemon juice, Dijon mustard, cayenne and 1/4 tsp salt until slightly thickened. Place the bowl over (not touching) gently simmering water and continue whisking constantly. The mixture should warm and thicken slightly, taking care not to scramble the yolks.

Finish hollandaise

Remove the yolk mixture from the heat. Very slowly (a few drops at a time to start), whisk in the warm clarified butter until the sauce becomes smooth and emulsified. If it thickens too much, whisk in 1–2 teaspoons warm water to adjust. Taste and season with remaining 1/4 tsp salt and additional lemon juice if desired. Keep warm in a thermos or over very low warm water (do not overheat).

Poached eggs

Bring 2 liters of water to a gentle simmer in a wide sauté pan. Add 2 tbs white vinegar and 1 tsp salt. Reduce heat so the surface has gentle ripples but not a rolling boil.

Crack each egg into a small ramekin or cup. Swirl the water gently to create a small vortex and carefully slip one egg into the center. Repeat for 2–3 eggs depending on pan size, leaving space between them.

Poach eggs 3 minutes for runny yolks or 3.5–4 minutes for slightly firmer yolks. Use a slotted spoon to lift eggs, gently blot under paper towel to remove excess water, and transfer to a warm plate. Keep warm in a shallow dish in a warm oven (80–90°C / 175–195°F) if not assembling immediately.

Bases and assembly

Split the English muffins and toast cut sides in a skillet with 1 tbs butter until golden and crisp. Alternatively, toast in a toaster and butter lightly.

Warm the Canadian bacon or ham in the same skillet for about 30–60 seconds per side until just heated and slightly caramelized.

To assemble each serving (serves 2): Place one toasted English muffin half on each plate, top with one slice of warm Canadian bacon, then one poached egg.

Spoon 2–3 tablespoons of warm hollandaise sauce over each egg. Sprinkle with chopped chives and a light grind of black pepper. Serve immediately.