Roast the bell pepper, chilies, shallot, garlic, and green onions on a baking sheet with olive oil, salt, and pepper.
Combine the roasted veggies with parsley, salt, cayenne, oregano, smoked paprika, lemon zest, lemon juice in a food processor and blend.
Add the red wine vinegar and slowly drizzle in ½ cup olive oil. Taste and adjust seasoning as needed.
Add the marinade to the chicken thighs, toss to coat, cover and refrigerate for at least 4 hours or overnight.
Roast the garlic head.
Cover the potatoes with cold water, season with salt, and boil until fork tender.
Roast the marinated chicken thighs.
Toss the broccolini with olive oil, salt, pepper, smashed garlic, and lemon juice. Add to the baking sheet with the chicken.
Peel and mash the potatoes, gradually adding the warm milk, butter, and roasted garlic. Stir in sour cream.
Make the glaze by combining the reserved marinade, chicken drippings, 1 tbsp butter, and 1 tbsp honey. Simmer until thickened.
