Best Sheet Pan Roast Chicken

Name: Best Sheet Pan Roast Chicken
Ingredients: 4 chicken thighs; 4 chicken legs; 1 whole lemon (squeezed); 1 bunch of thyme (leaves picked); 1 tsp garlic power; 1 tsp onion powder; 1 tsp paprika; salt (two big pinches); pepper (big pinch); 1 tbsp olive oil; 1/2 shallot (diced extra fine); 1/3 cup chicken broth or stock; 1/8 cup pan drippings; 1/2 tbsp butter