How to Make It
Bring a large, deep skillet filled with 2 inches of water to a simmer. Crack each egg into a cup and gently slide it into the water. Cook until the whites are solid but the yolks are still soft, 5 minutes. Using a slotted spoon, transfer the eggs to a paper towellined plate to drain.
Meanwhile, in a large skillet, heat the olive oil until shimmering. Add the pancetta and cook over moderately high heat until crisp, about 3 minutes. Add the shallot and cook until softened, 2 minutes. Remove from the heat and add the vinegar, tarragon and scallions.
In a bowl, toss the mesclun with the dressing; season with salt and pepper. Transfer the salad to plates, top with the eggs and serve with toast points.