Chop the olives. Wash capers and let dry. Briefly water the anchovies, drain well. Halve the chilli pepper, remove the stem and seeds and roughly dice the pulp.
Put everything in the blender and season with oregano and pepper. Puree finely and add enough olive oil to make a spreadable mixture.
Roast slices of white bread and brush with the tapenade. Garnish with capers and sprinkle with fleur de sel and drizzle with a little lemon juice.