1. Preheat the oven to 150 °C (th. 5).
2. In a pan, heat a knob of butter. Brown the chicken fillets over high heat for 5 minutes. Season with salt and pepper.
3. Let cool, then slice the fillets into thin slices, about 5 mm thick.
4. Boil the eggs in a pot of salted boiling water for 9 minutes. Let cool, then peel and cut into thin rounds.
5. Peel the tomatoes and slice them into thin slices.
6. Slice the lettuce leaves and cut the pickles lengthwise.
7. Remove the crust from the bread slices and toast them on one side under the broiler.
8. Assemble the club sandwich. Spread mayonnaise on one slice of bread. Top with tomato, egg, chicken, pickles, and lettuce. Spread mayonnaise on another slice of bread and place it on top of the filling. Finish with a slice of bread spread with mayonnaise.
9. Secure the sandwich with wooden picks.
10. Repeat the process for the other 3 sandwiches.
11. Cut the sandwiches in half or into four triangles.