Place chicken breast in slow cooker crockpot. Sprinkle with salt and pepper.
In a small bowl, combine peach preserves, barbecue sauce, mustard, and red chili flakes (if using).
Pour 1/2 of peach barbecue glaze all over the chicken. Cook on low heat for 4 hours or until temperature reaches 165 degrees.
Shred chicken and pour remaining glaze all over the chicken.
Serve warm with creamy parmesan mashed potatoes.
Notes
*May add 1/2 cup more BBQ sauce if you want it to be saucier. The peach jam comes through more, the less barbeque sauce.*I use hot brown mustard but you can use any variety of mustard