In a skillet over medium heat, cook the bacon until crispy. Remove and crumble, leaving the drippings in the skillet.

In the same skillet, add olive oil, apple cider vinegar, Dijon mustard, salt, and pepper. Stir to combine and heat through.

Add the torn romaine lettuce to the skillet and toss gently until wilted, about 1-2 minutes.

Transfer the wilted lettuce to a mixing bowl and add the cherry tomatoes, red onion, and crumbled bacon. Toss to combine.

Serve immediately on a serving platter.