Place a large Dutch oven or cast iron skillet over medium-high heat.

In a small bowl, combine salt, black pepper, granulated onion, granulated garlic, lemon pepper, chili powder, and cayenne pepper.

Lift the skin of the chicken thighs and generously season the meat on all sides with the prepared spice blend.

Add oil to the heated pot or skillet. Arrange the chicken thighs in a single layer and sear until golden brown on both sides, approximately 6 minutes per side. Once browned, remove the chicken and set aside.

Reduce the heat slightly and introduce butter and sliced onions to the pan, stirring to deglaze and release any flavorful bits from the bottom. Sauté the onions until they soften and turn translucent, about 5 to 7 minutes.

Sprinkle the flour and chicken bouillon powder over the onions, whisking continuously until fully incorporated into the butter and onions, forming a smooth paste.

Slowly pour in the chicken stock while whisking vigorously to ensure a lump-free, velvety gravy. Taste and adjust the seasoning with additional bouillon if necessary.

Bring the gravy to a gentle boil before returning the browned chicken thighs to the pot.

Cover with a lid, reduce the heat to low, and allow the chicken to simmer in the gravy for 1 hour. Stir occasionally to prevent sticking and ensure even cooking.

Once the chicken is tender and fully cooked through, serve hot alongside a generous portion of white rice. Spoon additional gravy over the top before serving.