Place peaches, cut-side up, in a large casserole dish
In a non-reactive prep bowl, whisk together the dark balsamic vinegar, orange juice, and honey. Pour over peaches and set aside to absorb for 15 minutes.
In a large sauté pan over medium-high heat, place peaches, cut-side down, along with the marinade. Cook about 3 minutes, or until slightly softened. If the peaches look like they may start to burn, lower heat. Transfer a peach half to each serving dish, add a dollop of crème fraîche, garnish of orange zest if desired and drizzle marinade from the pan over and around.