Heat the oven to 400°F. 

• Scrub or peel the sweet potato. Cut the potato in half lengthwise, then crosswise into ¼-inch-thick half-moons.

On a sheet pan, drizzle the sweet potato with 1 to 2 tablespoons oil, season generously with salt and pepper, and toss to coat. Spread in an even layer and roast, turning once halfway through, until tender and lightly browned, 20 to 25 minutes. Meanwhile, prepare the green beans and eggs.

• Trim the stem ends from the green beans if needed; cut the beans in half on the diagonal.

Bring a medium sauce pot of salted water to a boil. Add the beans and cook until just tender, 3 to 4 minutes. Using tongs or a slotted spoon, transfer to a colander and rinse under cold water. 

Return the water to a boil. Fill a small bowl with ice water. Carefully lower the eggs into the boiling water and cook for exactly 5 minutes for runny yolks (for firmer yolks, cook 1 to 4 minutes longer). Transfer the eggs to the ice water to cool. Carefully peel the eggs. While the beans and eggs are cooking, prepare the seafood.

• On a cutting board, using a small pot or bowl or a rolling pin, lightly crush the cumin seeds and coriander seeds; transfer to a plate. Season generously with pepper.
• Pat the seafood dry with a paper towel (if using scallops, rinse and drain, then pat dry); season generously with salt. Press the seafood into the cumin and coriander seeds, coating both sides. 

For tuna:

In a large frying pan over medium-high heat, warm 1 to 2 tablespoons oil until hot but not smoking. Add the tuna and cook, turning once, until lightly browned, about 1 minute per side for rare, 2 to 4 minutes per side for medium. Transfer to a cutting board to cool slightly, then cut into ½-inch-thick slices.

For scallops: 

In a large frying pan over medium-high heat, warm 2 to 3 teaspoons oil until hot but not smoking. Add the scallops and cook without turning until golden brown on one side and starting to turn opaque, 2 to 4 minutes. Turn and continue cooking for about 30 seconds for translucent or 1 to 2 minutes for opaque. Transfer to a plate. 

While the seafood is cooking, prepare the rest of the meal.

• Cut the olives in half lengthwise, checking for any pits.
• Cut the eggs in half lengthwise. 
• Coarsely chop the dill.

In a small bowl, stir together the sherry vinaigrette base, dill, and 1 to 2 tablespoons oil. Season to taste with salt and pepper. In a medium bowl, toss together the mixed greens and 1 tablespoon [2 TBL] vinaigrette (set aside the remaining vinaigrette for serving). 

Transfer the greens to individual bowls. Arrange the seafood, sweet potato, green beans, olives, and eggs in small piles on top of the greens. Drizzle with the remaining vinaigrette and serve.