Preheat the grill to high. Line a baking tray with foil, then sit a roasting rack on top. Brush the chicken with the olive oil and put it on the rack with the bacon. Grill for 3–4 min on each side until the chicken is cooked through, removing the bacon rashers once crisp. Set aside to cool a little.

Once cool enough to handle, use a sharp knife to carve the turkey escalope horizontally, at a slight angle, into 4 thin slices. In a small bowl, combine the mayonnaise and mustard.

Toast the bread until golden. Spread half the mustard mayonnaise over 2 slices of toast, then top with the sliced chicken and the rocket. Spread 2 more slices of toast with the remaining mustard mayonnaise, then put them on top of the rocket, mayo side up, to form 2 sandwiches. Top with the bacon and tomato, then finish with the remaining 2 pieces of toast. Secure with cocktail sticks, then cut each sandwich in half diagonally to serve.