Preheat the oven to 425F and position the oven rack in the middle of the oven.
Remove excess fat from the chicken thighs and pat them dry with a paper towel.
In a small bowl, combine the olive oil, salt, garlic powder, pepper, and Italian seasoning and set aside.
Season:
Place the potatoes, cherry tomatoes, and shallots (or onions) on the sheet pan. Drizzle half of the olive oil and seasoning mixture over the top, and with your hands, toss to coat them with the seasoning. Distribute them around the sheet pan.
Use the remaining olive oil and seasoning to season the chicken thighs. Place them on the baking sheet in between the potatoes.
Bake:
Roast the sheetpan meal for 30 minutes, opening the oven to stir the potatoes and veggies once during the last ten minutes of cooking. At this temperature, the thighs should be nice and golden. For extra-crispy skin, turn the oven on to BROIL, and let them crisp up under the broiler for 1-2 minutes.
When the chicken thighs' internal temperature reaches 175F, remove the pan from the oven and serve.