01 - Pat chicken thighs dry with paper towels. Season thoroughly with salt, black pepper, smoked paprika, and dried thyme.
02 - In a large skillet or Dutch oven set over medium-high heat, add olive oil and unsalted butter until melted and shimmering.
03 - Place chicken thighs, skin-side down, into the hot pan. Sear until the skin is golden brown and crisp, about 6 minutes per side. Remove chicken and set aside.
04 - Add sliced yellow onions to the same pan. Cook, stirring occasionally, until onions are soft and deeply golden, about 8 minutes. Incorporate minced garlic and sauté for 1 minute until fragrant.
05 - Sprinkle flour evenly over softened onions. Stir and cook for 1 to 2 minutes to remove any raw flour taste.
06 - Gradually stream in chicken broth, whisking constantly to prevent lumps. Bring the mixture to a gentle simmer, scraping any browned bits from the bottom.
07 - Nestle the seared chicken thighs, skin-side up, into the simmering gravy. Spoon some of the sauce and onions over the meat.
08 - Cover with a tight-fitting lid. Reduce heat to low and simmer for 25 to 30 minutes, or until chicken is fully cooked and gravy has thickened.
09 - Taste the sauce and adjust salt or seasoning if necessary.
10 - Plate the chicken thighs and lavish with spoonfuls of onion-rich gravy. Garnish with chopped fresh parsley if desired.