Toasting gives dishes a nutty undertone.
For the seasoning, in a small bowl, mix all the ingredients.
Preheat the broiler. Place the bagels on a rimmed baking sheet and broil until toasted, 3 to 5 minutes per side.
In a medium bowl, mix the cream cheese, radishes, scallions, dill and half the seasoning.
Slather the bagels with the cream cheese mixture. Form bagel sandwiches with the lox, tomato, red onion, a sprinkle of pepper and the remaining seasoning.