2) Lay the rasher bacon on a baking sheet, and bake for 20 to 25 minutes, or until crisp. Dry on paper towels and large dice.
2) For the dressing, place the egg yolk, mustard, garlic, lemon juice, salt, and pepper into the bowl of a food processor fitted with steel blade. Process until smooth. With the food processor running, slowly pour the olive oil through the feed tube (as though you were making mayonnaise) and process until thick. Add 50g grated parmesan and pulse 3 times.
3) Toss the lettuce with enough dressing to moisten well. Divide the lettuce among 4 plates. With a very sharp knife or a vegetable peeler, shave the parmesan into large shards and arrange them on the lettuce. Sprinkle the diced rasher bacon over the salad and serve.