Mix the chicken marinade ingredients together is a glass measuring cup or small bowl. Mix rapidly to combine.
Place the skinless boneless chicken thighs into a 1 gallon Ziploc bag, and add the marinade. Turn and mix the bag until the chicken is well coated, and set aside for 30 minutes to overnight.
Preheat your grill to medium high.
To make the salsa, clean and wash the peaches, then chop them into small chunks. Mix the chopped peaches with the diced red bell pepper and the remaining salsa ingredients. Stir well to combine and evenly distribute the ingredients.
Grill the chicken thights, about 4-6 minutes per side, turning once. When cooked through, remove from the grill and slice into long thin strips
Heat the flour tortillas briefly on the grill grates to toast them lightly.
To assemble, place the sliced chicken on top of the tortillas, and top with peach salsa. That’s it! You could add a scoop of sour cream for a bit more tang, but the salsa is pretty complete on it’s own.