1 to 1 1/4 pound boneless, skinless chicken breasts, Salt, 2 Tbsp olive oil + more for lightly coating chicken, 1 Tbsp butter, 1 cup sliced shallots, 1/2 cup dry white wine (can sub chicken stock), 1/2 cup water, 4 Tbsp Dijon mustard, smooth or whole grain or a mixture of both, 1 teaspoon dried thyme, 1/4 cup heavy cream
1 Remove chicken breasts from package and sprinkle with salt. Remove the tenderloin from each breast and set aside. Cut each chicken breast into 3 pieces, approximately the same size. Coat with just a little olive oil. Place the breast pieces between two pieces of plastic wrap or parchment paper and use a mallet, empty wine bottle, or rolling pin to pound the chicken pieces to an even thinness of about 1/4 inch. Repeat with the tenderloin pieces.
2 In a large, heavy-bottomed sauté pan, heat the olive oil on medium high to high heat. Stir in the butter. When the butter is foamy, add the chicken pieces to the pan. Do not crowd the pan, if necessary work in batches. Lightly brown chicken on one side, turn over and brown the other side. Do not overcook the chicken. The pieces are thin and they will cook quickly. Remove the chicken pieces from the pan and set aside while you make the sauce.
3 Add sliced shallots to the pan. Lower the heat to medium. Stir to coat with the remaining fat in the pan. Cook until softened, about 5 to 6 minutes.
4 Add white wine to the pan and increase the heat to high. When most of the wine has evaporated, add the water, the mustard, and the dried thyme. Reduce by half.
5 Lower the heat to low. Add the chicken back to the pan and coat with the sauce. Remove the pan from heat and drizzle in the cream. Taste and adjust seasonings, adding more salt if necessary.
Serve with egg noodles (not for gluten-free version), rice, mashed potatoes, puréed celery root or parsnips (or serve alone or with vegetables for low carb version).