gluten freePreheat the oven
Set the oven to 400°F (200°C) so it is fully hot by the time the chicken and potatoes are ready to roast. Place a large roasting pan or baking dish nearby so assembly is easy.
Wash the produce
Rinse the Yukon Gold potatoes well to remove any grit before peeling. If you are using the garnish, rinse the oregano and lemon too, then dry them so they are ready for later.
Prep the vegetables
Peel and finely mince the garlic. Peel the potatoes, cut them into large, even chunks, and place them in a bowl of cold water to soak for 15 minutes; this helps wash off excess surface starch so they roast more cleanly. If using the garnish, pick the oregano leaves from the stems and slice the lemon into wedges or thin rounds.
Whisk the marinade
In a large bowl, whisk together the olive oil, lemon juice, Dijon mustard, honey, dried Greek oregano, dried thyme, fine sea salt, black pepper, and the minced garlic until the mixture looks smooth and well blended.
Coat the chicken
Add the chicken thighs to the bowl and turn them thoroughly in the marinade, making sure all sides are coated. Let the chicken sit while the potatoes finish soaking, or refrigerate it for up to 30 minutes if you have a little extra time.
Drain and coat potatoes
Drain the soaked potatoes and pat them very dry with a clean towel or paper towels; they should feel dry on the surface, not damp. Transfer them to a separate bowl and spoon over a little marinade, tossing until the pieces are lightly and evenly coated.
Roast until golden
Spread the potatoes in the roasting pan in an even layer. Nestle the chicken on top of and between the potatoes, skin side up, then pour any remaining marinade over everything. Roast for 20 minutes, then remove the pan and carefully turn or stir the potatoes so they brown evenly, keeping the chicken skin side up. Return the pan to the oven and continue roasting for 25 to 35 minutes, until the chicken is cooked through, the skin is golden, and the potatoes are tender and browned. The thickest part of the chicken near the bone should reach 165°F (74°C). If you want deeper color at the end, broil for 1 to 3 minutes, watching very closely so nothing burns.
Rest and serve
Let the pan rest for 5 to 10 minutes so the juices settle a bit. Scatter over the fresh oregano, add the lemon wedges or slices if using, and serve warm with the pan juices spooned over the chicken and potatoes.
