Let chicken stand at room temperature for 20 minutes. Sprinkle with salt and pepper. In a 12-inch cast-iron skillet, heat 3 tablespoons oil over medium-high heat. Add chicken, skin side down; cook until browned, 6 to 8 minutes. Turn chicken over; add onion, persimmons, and herb sprigs to pan. Cook until chicken is browned, about 3 minutes. Remove from heat.
In a small bowl, whisk together syrup, chopped herbs, and remaining ¼ cup oil. Brush half of glaze onto chicken.
Bake until an instant read thermometer inserted in thickest portion registers 165°, 30 to 40 minutes, brushing with remaining glaze halfway through baking. Garnish with thyme and rosemary, if desired.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/roasted-chicken-thighs-persimmons-red-onion/