This appetizer of extra-large scallops also makes a perfect light lunch or dinner. Prosciutto is a cured Italian ham. Coating the scallops with oil and wrapping them in prosciutto helps retain their moisture and keep them tender.
Preheat oven to 400°F.
Cut the tomato in half and the shallot in quarters. Place in a small bowl with 1 tablespoon of olive oil and salt and pepper. Place the tomato, cut side down, and shallot pieces on a baking sheet. Roast until the tomato skin is slightly brown. Remove from the oven and set aside to cool.
Place the tomatoes, shallots and vinegar in a blender and blend well. Season with salt and pepper. With the blender running, slowly add ¼ cup of olive oil, until the mixture emulsifies.
Season scallops with salt and pepper and wrap each scallop in a piece of prosciutto.
Heat a medium sauté pan or skillet to medium-high. Add the remaining 1 tablespoon of the oil. When oil is shimmering, carefully place the scallops in the pan and sear on each side, for about 2 minutes per side. Set aside.
In a large sauté pan or skillet over medium-high heat, heat 1 tablespoon of olive oil. Add the chopped radicchio and endive and sauté, stirring occasionally until just wilted, about 5 minutes. Stir in 3 tablespoons of the roasted-tomato vinaigrette.
To serve, place one-quarter of the radicchio-endive mixture on each of four plates. Top each with 2 scallops and drizzle each with 1 tablespoon of the vinaigrette.