In a medium bowl, combine peach preserves, bourbon, olive oil, soy sauce, apple cider vinegar, Dijon mustard, garlic, salt, black pepper, and red pepper flakes. Set aside half of the mixture (about ¾ cup) and refrigerate for later use.

Place the salmon fillets in a resealable plastic bag and pour in the remaining half of the marinade. Seal the bag and mix well to coat the salmon. Refrigerate for at least 30 minutes, up to 1 hour.

Preheat the oven to 375°F.

In a medium, oven-safe skillet over medium-high heat, add oil. Once hot, carefully place the marinated salmon fillets in the skillet, skin side up. Cook for about 2-3 minutes until seared and golden brown.

Flip the salmon fillets so the skin side is down. Add the sliced peaches to the skillet. Cook for 2-3 more minutes, allowing the peaches to soften and the salmon skin to sear slightly.

Remove skillet from heat. Pour the reserved peach marinade into the skillet, evenly distributing it over the salmon and peaches.

Transfer the skillet to the preheated oven and bake for 12-15 more minutes or until the salmon is cooked through, checking at 12 minutes.

Once cooked, remove from the oven and serve immediately.