Wash the lettuce, then cut it in half through the middle of the stem. Cut the halves in half again through the stem, then put the quartered lettuce in a large bowl of ice water. This not only chills the lettuce, it will make the lettuce extra crisp.
Fry the bacon until crisp and drain on a paper towel.
To make the dressing, crumble the blue cheese into a small bowl, then add the Marscarpone, yogurt, mayonnaise, and milk. Stir together until combined, leaving a few chunks of blue cheese. If you want your dressing to be more pungent, you can leave out the marscapone and just use 100 grams of blue cheese. Taste the dressing and add salt as needed.
To assemble the salad, drain the wedges of lettuce well, shaking out any excess water. Drizzle some dressing on top, then sprinkle the bacon, and blueberries on top. Finish with some fresh ground black pepper. You can also crumble on more blue cheese.