In a bowl, whisk together the olive oil, balsamic vinegar, garlic, Italian seasoning, honey, Dijon, salt, and pepper.
Add the chicken thighs and toss to coat. Marinate 15 to 30 minutes, or up to 12 hours in the fridge (not longer!)
Oven method (main): Preheat oven to 425F. Arrange the thighs in a single layer in a baking dish and pour remaining marinade over the top.
Bake 22 to 28 minutes, until the chicken reaches 165F and the edges caramelize. Broil 2 to 3 minutes for extra color if you like.
Rest 5 minutes, drizzle with balsamic glaze, and serve.