Niçoise Toast

4 large eggs
Juice from 1 lemon
1 lb. tomatoes, cut into bite-size pieces
1 medium shallot, thinly sliced
A pinch of sugar
Kosher salt
1/2 cup mayonnaise
1 small garlic clove, finely grated
1 1/2 tsp. sherry vinegar or red wine vinegar
1/2 tsp. hot smoked Spanish paprika
4 Tbsp. extra-virgin olive oil, plus more for drizzling
4 slices sourdough bread
2 (6–7-oz.) jars oil-packed tuna, drained
Flaky sea salt
Freshly ground black pepper
1/2 cup torn mixed tender herbs (such as dill, parsley, basil, and/or tarragon)
1/4 cup oil-cured black olives, pitted, flesh torn

Bring a medium saucepan of water to a boil.
Gently lower eggs into pot with a slotted spoon and cook 8 minutes.
Transfer to a bowl of ice water and let cool. Peel eggs; set aside.
Toss lemon juice, tomatoes, shallot, sugar, and a pinch of kosher salt in a medium bowl.
Whisk mayonnaise, garlic, vinegar, and paprika in a small bowl; season with kosher salt.
Heat 2 Tbsp. oil in a large skillet over medium until shimmering.
Add 2 slices of bread and cook, adjusting heat as needed, until bottoms are deeply browned, about 3 minutes. Transfer to a platter and sprinkle fried side with kosher salt.
Repeat with another 2 Tbsp. oil and remaining slices of bread.
Spread mayonnaise over toasted side of bread.
Top with tuna and tomato mixture; spoon some of the juices over.
Tear each egg into 3 or 4 pieces and arrange on top; season with sea salt and pepper.
Scatter herbs and olives over; drizzle with oil.
Do Ahead
Paprika mayonnaise can be made 2 days ahead. Cover and chill.