Preheat oven to 425°F. Season 4 chicken thighs with salt all over and set aside. Cut 2 medium yellow potatoes into wedges, 1 small fennel bulb into planks and roughly chop 3 garlic cloves.
Transfer the potatoes and fennel to a 9x13" baking dish. Season with a generous pinch of salt and 1/2 tsp fennel seeds, toss to coat. Cut 1/2 the blood orange into 6 thin slices and shingle over the potatoes and fennel. Juice the remaining orange into a small jar and top with 6 tbsp olive oil, chopped garlic and a generous pinch of salt. Shake, or mix, until emulsified.
Using a paper towel, pat the chicken thighs dry and transfer to the baking dish (skin-side up). Pour the orange marinade over the chicken thighs. Then fill the jar with 2 tbsp water and shake, then pour the water around the sides of the dish, avoiding the chicken, aiming for the veggies resting at the bottom.
Place pieces of butter (about 4 tbsp total) around the dish and bake at 425°F for 20 minutes, or until the skin starts to brown. Reduce heat to 400°F and bake for another 20 minutes, or until the skin is crispy and the potatoes are fork tender. An instant-read thermometer placed into the thickest part of the chicken should read 160-165°F. If the chicken finishes before the potatoes are ready, remove the chicken, place the tray back in the oven, and continue cooking, while the chicken rests. Serve with chopped parsley and enjoy!
