Finely chop the tomatoes. Mix the chopped tomatoes with some oil from the jar until a paste is formed.
Rinse the frisee and tear into small pieces.
Blanch the radish in boiling salted water for about 2 minutes. Cool in ice water and pat dry. Slice thinly and cut out 8 circles with a round cookie cutter or ring about 8 cm (approximately 3 inches) in diameter.
Cut the salmon into small cubes, mix with chives, shallot, oil and lemon juice. Season with salt and Tabasco.
Set the ring mold on a plate. Spread a thin layer of tomato paste as the base. Spoon some salmon over the tomato paste and top with a radish circle. Spoon another layer of salmon and top with another radish circle. Top with a final layer of salmon. Press lightly and remove the ring mold. Continue with the three other plates. Garnish each with frisee lettuce and one teaspoon of caviar before serving.