Spray a 12-inch nonstick skillet with cooking spray and set over medium-high heat.
In small bowl, whisk together flour with pepper. Coat chicken with flour.
Brown chicken in a single layer in prepared skillet until golden on bottom, about 6 minutes. Turn chicken and brown on the other side, about 4 more minutes. Remove chicken from skillet and set aside. Note: you may have to brown the chicken in two batches.
Pour broth into hot skillet and scrape up any browned bits with a wooden spoon. Return chicken to skillet, cover, and reduce heat to low. Simmer until heated through, about 3 minutes.
Stir in lemon juice and capers and heat for 30 seconds.