Prepare the hollandaise base. Separate 4 eggs, placing the yolks into a heatproof bowl that fits snugly over a small saucepan. Whisk the yolks with 1 tablespoon of water until they turn a pale, creamy yellow — the mixture should feel slightly thicker and look like a smooth custard.

Cook the hollandaise sauce. Melt the butter in a small pan over low heat until it's completely liquid and you see tiny bubbles around the edge — it should smell nutty, not burnt. Slowly drizzle the hot butter into the egg yolks, whisking constantly. The sauce will thicken and turn glossy, almost like a thin mayonnaise. Stir in the lemon juice, salt, and cayenne pepper. Keep it warm by placing the bowl back over the pan of hot (not boiling) water.

Poach the eggs. Fill a large frying pan with water about 5cm deep and bring it to a gentle simmer — you want tiny bubbles rising to the surface, not a rolling boil. Add the white vinegar. Crack 4 eggs into separate small cups. Gently slide each egg into the water, spacing them apart. Cook for 3 to 4 minutes — the whites should be fully set and opaque, while the yolks will jiggle when you gently poke them with a spoon.

Toast the muffins. While the eggs poach, toast the English muffin halves in a toaster or under the grill until they are golden brown and the edges are crisp. You should hear a satisfying crunch when you press them.

Warm the chicken. Quickly heat the shredded chicken in a small pan over medium heat for 1 to 2 minutes, just until it's warm and you can smell the meat heating through. Do not let it dry out.

Assemble the dish. Place two muffin halves on each plate. Divide the warm chicken evenly over the muffins. Using a slotted spoon, lift each poached egg out of the water, letting the excess water drip off, and place one on top of each muffin half. The egg should feel firm on the outside but soft when you touch it. Spoon the warm hollandaise sauce generously over the eggs, letting it cascade down the sides. Garnish with fresh chives.