01 - Bring a medium saucepan of water to a gentle boil. Carefully lower in the eggs and simmer for 6 to 7 minutes for soft-boiled yolks. Transfer eggs to an ice bath and let cool for 2 minutes, then peel carefully.
02 - While eggs cook, toast the bread slices until golden and crisp on both sides.
03 - In a small bowl, whisk together olive oil, lemon juice, Dijon mustard, salt, and pepper until emulsified.
04 - In a large bowl, toss mixed greens and cherry tomatoes with half of the dressing until evenly coated.
05 - Arrange toasted bread on serving plates. Top each with sliced avocado and dressed greens mixture.
06 - Halve the soft-boiled eggs and place on top of each plate. Drizzle with remaining dressing and garnish with chopped chives and flaky sea salt.