Preparation
Coat a grill rack or broiler-pan rack with cooking spray. Preheat the grill or broiler.
In a cup, combine the chili powder, cumin, and salt. Cut two 1/2"-deep slashes in each side of the chicken tenders. Rub the spice mixture over the chicken, pressing it into the slits. Place the chicken in a baking pan and coat completely with cooking spray. Let stand for 10 minutes.
In a food processor, combine the cilantro, parsley, almonds, garlic, chile pepper, and salt. Process until chopped. While the processor is running, add the lime juice and oil through the feed tube, stopping the machine once or twice to scrape down the sides of the container until the sauce is smooth. Pour the sauce into a bowl. Stir in the water, cover, and chill until ready to serve.
Place the chicken on the prepared rack and grill or broil 6" from the heat, turning several times, for 15 minutes, or until a thermometer inserted in the thickest portion registers 170°F and the juices run clear. Serve with the sauce and garnish with the cilantro.