Place the chicken in a pan or ziploc bag and pour Italian dressing over, and allow to marinate overnight or at least 2 hours.
Char jalapeño peppers in the oven on broil for 5 minutes or until skin is charred, turning once halfway through. Alternately, you can char peppers on the grill, or skip this step entirely.
Allow peppers to cool until cool enough to handle. Slice of tops and cut in half, lengthwise. Remove seeds and membranes if desired.
Butterfly a chicken breast and open to lay flat.
Spread 1-2 ounces of cream cheese on a jalapeño half and top with the other half.
Place the stuffed jalapeño inside of the butterflied chicken. Close the chicken, enclosing the pepper inside.
Starting at the thick end of the chicken breast, secure a piece of bacon with a toothpick and wrap around. At the end of the first slice of bacon, overlap with another piece of bacon and secure with another toothpick. Continue wrapping the second slice of bacon and secure the end with another toothpick. Wrap a 3rd slice of bacon if the chicken doesn't feel securely wrapped.
Repeat with other 3 chicken breasts.
Grill on high heat for 20 minutes on each side. Do not move once you have placed the chicken on the grill, aside from turning it over.
Remove all toothpicks before serving, and enjoy!