- 1/4 cup buttermilk or fat-free plain yogurt
- 2 tablespoons low-fat mayonnaise
- 1/4 cup blue cheese
- 2 tablespoons chopped fresh chives or scallion greens
- 4 plum tomatoes, thinly sliced
- 1 small red onion, halved and thinly sliced
- 3/4 pound thinly sliced lean roast beef
- 4 leaves lettuce
- 4 onion sandwich buns
- In a small bowl, combine the buttermilk or yogurt, mayonnaise, cheese, and chives or scallion greens.
- Heat a large nonstick skillet coated with cooking spray over medium-high heat. Add the tomatoes and onion and cook for 3 minutes per side, or until lightly charred.
- Layer the roast beef, onion, tomatoes, and lettuce on the bottoms of the buns. Drizzle with the blue cheese dressing. Cover with the bun tops.