Searing scallops lends them extra flavor, but the key is not overcrowding the pan, which lowers the cooking temperature. If you see juice exuding from the scallops as they cook, the pan’s temperature is too low and they are steaming, not searing (they will likely overcook before they can take on any flavorful color.) Cook the scallops in batches, and remove them from the pan before the second side has a chance to completely brown – you don’t want to overcook them.
In a glass or ceramic bowl, combine the herbs, garlic, and lemon juice. Slowly whisk in the olive oil. Season with salt and pepper. Set aside.
Pat the scallops dry and season them with salt and pepper. In a heavy, large skillet, heat 1 tablespoon of the oil over medium-high heat. Add a third of the scallops and cook, without moving them, until they are golden brown on the bottom, about 1 minute. Turn and cook the other side until the scallop is an opaque in the center (the other side may not be browned before the scallop is cooked). Transfer the scallops into a large glass or ceramic bowl. Cook the remaining scallops in the same way in two more batches, using 1 tablespoon oil for each batch; transfer them to the bowl as they are cooked.
Add the diced bell peppers to the scallops. Toss with just enough herb dressing to lightly coat. Serve immediately in scallop shells or in small martini glasses, garnished with fresh herbs.