Sauté the Spinach: Heat olive oil in a pan over medium heat. Add garlic (optional), then spinach. Cook until wilted (2–3 minutes). Season with salt and pepper. Set aside.
Poach the Eggs: Fill a saucepan with water, add a splash of vinegar, and bring to a light simmer. Crack each egg into a cup, then slide it into the water. Cook for 3–4 minutes until whites are set. Remove with a slotted spoon.
Make the Hollandaise: Whisk egg yolks and lemon juice in a heatproof bowl. Place over simmering water (don’t let the bowl touch the water). Slowly whisk in melted butter until thick and smooth. Add salt and cayenne.
Assemble the Dish: Place toasted muffin halves on plates. Top with spinach, a poached egg, and spoonfuls of hollandaise sauce.
Serve Immediately: Garnish with chopped chives or paprika if desired. Serve warm and enjoy!