2 cups bread cubes (1/2-inch cubes)
1/4 cup extra-virgin olive oil
1 teaspoon Dijon mustard
1 tablespoon balsamic vinegar
Salt and freshly ground pepper
1 head romaine lettuce, chopped into bite-size pieces
1 small seedless cucumber, thinly sliced
Preheat the oven to 350°. On a baking sheet, toss the bread cubes with 1 tablespoon of the olive oil and toast for about 10 minutes, stirring once, until golden. Let the croutons cool.
In a large bowl, whisk the mustard with the balsamic vinegar. Gradually whisk in the remaining 3 tablespoons of olive oil and season with salt and pepper. Add the romaine, cucumber and croutons, toss well and serve.