Combine Dijon mustard, paprika, salt and pepper in a small bowl, to make a paste. Spread the paste evenly on both sides of chicken breasts. Set aside.
In a large skillet, cook chopped bacon on medium-high heat just until it starts to brown. Remove to a plate, leaving bacon fat in a skillet. To the same skillet, add chopped onion and cook in bacon fat until softened. Remove to the same plate, with bacon.
Add 1 tablespoon olive oil to the same, now empty, hot skillet. Cook chicken breast (with mustard paste on it), on medium heat, about 1.5 minutes on each side. The chicken will not be done as you will continue cooking it in the next step. Remove chicken to a plate.
To the same skillet, add 1 and 1/2 cups chicken broth, bring to boil, scraping the bottom of the pan. Add back bacon and onions, mix well. Add back the chicken breast, reduce the heat to low-medium and cook for about 15-20 minutes, turning chicken once, until chicken breast is fully cooked and no longer pink in the center.