Place water and tea bag in a microwave-safe measuring cup or bowl. Microwave for 60-90 seconds, until water is hot. Allow tea to steep for 5 minutes or longer. (Tea doesn't need to be hot, so don't worry about it cooling.)

Preheat oven to 425.

In a non-stick, cast-iron skillet, heat 1 Tbs. olive oil over medium-heat until very hot. Season chicken with salt and pepper, and then place skin-side down in the skillet, searing until golden, about 2 minutes. Transfer to a plate.

Add tea, honey, and mustard, stirring with a wooden spoon to scrape up any bits stuck to the bottom of the skillet. Simmer for 5 minutes, reducing slightly. Stir in butter.

Add apples and sweet potatoes. Sprinkle with salt and pepper. Nestle chicken thighs into apples and potatoes. Sprinkle with rosemary.

Transfer skillet to oven and bake until chicken reaches 165F at its thickest part, 22-26 minutes. Transfer chicken thighs to a clean plate. Cover with foil.

Stir apple-sweet potato mixture and return to oven for another 10-15 minutes, until sweet potatoes are cooked throughout.

Serve hot, with pan drippings drizzled over chicken.