In a medium bowl combine hard boiled eggs, red onion, cilantro and chives.
Gently stir in mayonnaise, mustard, lime juice, tabasco sauce and curry powder until well combined. Add salt and pepper to taste.
Spread egg salad on 4 slices of sourdough bread.
Melt ½ tablespoon butter in a skillet over medium heat.
Fry 1 egg over medium, until the yolk is still slightly runny. Repeat with the remaining butter and eggs.
Place 1 fried egg on top of each of the egg salad sandwiches. Top with remaining 4 slices of bread. Slice in half and serve.