Preheat oven to 350 degrees F (175 degrees C). Bring a saucepan of lightly salted water to a boil. Add chicken breasts, and boil until easily shredded, about 20 minutes.
Saute onion in a medium saucepan until soft. Remove from heat and stir in salsa, then stir in cheese until melted. Add chicken and mix all together.
Roll out biscuits individually, adding a little of the chicken mixture to each one; then roll up, secure with toothpicks and place on a lightly greased cookie sheet.
Bake at 350 degrees F (175 degrees C) for about 10 minutes, or until biscuits are golden and hot.
