Step 1

In a medium bowl, stir together peach preserves, olive oil, soy sauce, apple cider vinegar, Dijon mustard, garlic, salt, black pepper, and red pepper flakes. (This makes about 1 1/2 cups).

Step 2

Reserve half of the mixture, and refrigerate. The remaining peach mixture will be used to marinate the chicken.

Step 3

Pat chicken breasts dry and pound each to about ½-inch thickness.

Step 4

To a resealable plastic bag, add the chicken and sliced red onions. Pour the marinade into the bag, seal, and mix to coat.

Step 5

Place the marinating chicken in the refrigerator for at least 30 minutes, up to overnight.

Step 6

When ready, preheat the oven to 375°F.

Step 7

To a large oven-safe skillet over medium-high heat, add oil. Once hot, add the entire contents of the marinated chicken bag to the skillet. Sear the chicken for a few minutes on each side, or until golden brown.

Step 8

Pour the reserved peach marinade over the chicken breasts in the skillet. Arrange 4-5 sliced peaches on top of each chicken breast, and nestle the remaining peaches into the pan around the chicken.

Step 9

Transfer the skillet to the oven. Roast for 25-30 minutes, or until the chicken reaches an internal temperature of 165°F.