Slice the pork loin into rounds no more than 1-inch thick. Lightly salt and pepper the meat and set aside.
In a food processor or blender, process dates, lemon zest, garlic cloves, olive oil and vinegar until blended as much as possible. The vinaigrette will have a thick, chunky texture.
Ready the salad greens in a bowl.
Heat a pan on medium-high, add the pork and as the first side cooks, spread about 1 teaspoon of the vinaigrette onto each piece. After three minutes, flip the pork medallions and cook just a few minutes more, so the outside of the meat is browned but the inside is still a bit pink.
Toss the salad greens with the remaining vinaigrette and divide onto plates. Top with the pork.
