Lay the bacon in a large nonstick skillet and cook over medium heat until golden and crispy, about 5 minutes per side. Transfer to a paper towel-lined plate to drain. Chop and set aside.
Separate the endive leaves and arrange 14 large spears on a serving platter. Set aside the remaining leaves.
Divide the tomatoes evenly between the endive spears. Drizzle with the blue cheese dressing. Top with the red onion, bacon and walnuts. Season with salt and pepper. Chop the remaining endive leaves and use them to garnish the platter before serving.