How to Make It
Using a cookie cutter or shot glass, cut a 3-inch hole in the center of each slice of bread. Melt the butter in a large nonstick skillet over medium heat. Place the bread slices in the skillet, crack an egg into the center of each, and cook until the bread is golden and the whites are set, 1 to 2 minutes per side.
Dividing evenly, top with the smoked salmon, crème fraîche, capers, and red onion; season with ¼ teaspoon pepper.