Warm Chicken Salad with Raspberry Vinegar

2 Filets Skinless chicken breasts
12 Baby spinach leaves
3 Tbsp. Olive oil
3 Tbsp. Pine nuts
1-1/2 Tbsp. Raspberry red wine vinegar
1/2 Tbsp. White wine vinegar
1 Cup Small lettuce leaves, torn
Pepper

Cut chicken into fine strips. Wash and dry spinach leaves, discarding any hard stalks. Heat 2 Tbsp. of olive oil in a skillet. Stir-fry chicken for several minutes. Add spinach and cook for about 1 minute, or until barely wilted. Add pine nuts and cook for 1 more minute. Spoon the contents of the pan onto serving plates. Pour the vinegars into the pan with the remaining 1 Tbsp. of oil. Season with pepper and stir until mixed. Lightly toss with the torn lettuce leaves. Pour over the mixture on the plates and serve immediately. Top as desired.