Preheat the grill to high heat
Rub the flank steak on both sides with 1 tbsp olive oil and season with salt and pepper
Place the steak onto the hottest part of the grill and sear one side for about 4 minutes.
Turn the steak over and cook for a further 3-4 minutes or until a thermometer reads 130 degrees.
Transfer the steak to a plate and cover loosely with foil.
Let the steak rest while you build the rest of the salad.
Remove the outer leaves from the romaine and red leaf lettuce. Rinse heads of lettuce under cool water and pat dry
Chop the root end off each lettuce, discard, and then roughly chop the rest of the lettuce into chunks.
Lay the lettuce on a large board or in a salad bowl.
Slice the hard boiled eggs in half and then into quarters and place two piles on top of the lettuce.
Repeat with the bacon and blue cheese.
Cut the cherry tomatoes in half and add to the lettuce.
Slice the flank steak across the grain into thin strips and arrange on top of the lettuce.
In a small bowl, whisk together the remaining olive oil, red wine vinegar and Dijon mustard until creamy.
Season with salt and pepper.
Serve the salad with the dressing on the side.