Preheat the grill to high.
Grill the speck on a baking sheet for 4 minutes until crisp and drain on kitchen paper.
Butterfly the chicken breasts, season with salt and pepper, and brush with olive oil.
Cook chicken on a hot griddle pan for 3 minutes per side until cooked through.
Fry bread cubes in butter until golden brown.
Separate and cut the lettuce into chunky pieces.
Simmer garlic in wine for 5 minutes until soft and let cool.
Blend garlic, wine, egg yolks, anchovy, and cheese until smooth.
Emulsify the oil into the mixture slowly, then stir in mustard and seasoning.
Toss lettuce, croutons, and speck in the dressing and top with sliced chicken.