1Slice the chicken breast into long 1/2 inch wide
2To make a marinade, drop the garlic cloves and jalapeno peppers through the feed tube of a food processor with the chopping blade in place and the motor running until chopped finely (10 seconds or so).
3Add the remaining ingredients and process until smooth (about another 10 seconds.)
4Pour the marinade over the chicken and let marinate for 2 hours at room temperature or overnight in the refrigerator, turning occasionally.
5Preheat the oven broiler.
6Drain the chicken, reserving the marinade.
7Arrange the chicken on a rack on a broiler tray and broil 3 inches from the heat source for 5 minutes; turn, baste with marinade, and broil for another five minutes.
8Serve with warmed tortillas, shredded lettuce, shredded cheese, chopped tomatoes and salsa verde.