Prep: Wash the lettuce and cucumber, and peel the cucumber (if desired). Chop the lettuce into 1-inch squares by stacking trimmed leaves on a cutting board and cutting across the leaves in crisscrossed fashion. Slice the cucumber into half or quarter moons and thinly slice the red onion. Chop the cold cuts into small squares, as well as the cheese (if using).
Mix: Place all ingredients in step 1 into a large mixing bowl and then drizzle with olive oil and squeeze the lemon over everything. Add the sea salt and use a large wooden spoon or just your clean hand to mix everything together until the lettuce is well coated with dressing.
Enjoy: Divide the salad among serving plates, and enjoy immediately!
Notes
Meal prep: To make this salad ahead, place the chopped lettuce, cucumbers, onion and cold cuts in bowl or a mason jar with a lid. In a separate smaller container with a lid, add the remaining ingredients for the dressing. Store both up to 24 hours in advance, and then pour the dressing over your salad and shake to mix. Note: you may need to wait for the olive oil to liquefy after storing the fridge; if you put your hand around the container to warm it up, that should speed up the process.