For the vinaigrette, combine the balsamic vinegar and black pepper in a small bowl. Briskly whisk in the olive oil to emulsify. Set aside.
For the salad, add the mixed baby greens to a large mixing bowl and add 2-4 tbsp. of the balsamic vinaigrette (depending on how well you like it coated in dressing). Gently toss to coat.
Divide the dressed greens onto two separate plates. Arrange the cucumber, gorgonzola, avocado, almonds, apple and croutons atop the greens. Alternately, you can toss all the ingredients together instead of just adding the balsamic vinegar to the greens. Either way is fine.