Step 1 Trim the chicken thighs of any excess skin and fat, pat dry and season lightly on both sides with a pinch of salt.
Step 2 Heat the olive oil in a large saute pan over medium heat. When it is quite hot, add the chicken thighs, skin side down and brown well, about 15 minutes. If the chicken sticks to the pan, keep cooking: When the skin has browned enough, it will release. Turn and cook on the other side just until it loses its raw appearance, about 5 minutes. Remove to a plate and keep warm.
Step 3Pour off all but about 1 tablespoon of the fat and return the pan to the fire. Remove the sausage from the skins and crumble into the pan in hazelnut-sized chunks. Cook, stirring occasionally, until the sausage is well browned on all sides, about 10 minutes.
Step 4Add the onion and cook until it wilts, about 5 minutes. Add the garlic and cook until fragrant, about 3 minutes.
Step 5Add the red wine and cook, stirring and scraping the bottom of the pan to release all the browned bits. Continue cooking until the wine reduces to a syrup, about 5 minutes.
Step 6Add the tomatoes and stir them in. Cook until they begin to change color from bright red to brick, about 5 minutes. Return the chicken to the pan, skin side up, and scatter the green olives into the sauce.
Step 7Reduce the heat to low and cook until the chicken can be penetrated easily with a paring knife or carving fork, about 30 minutes. Taste and add more salt if needed and sprinkle with parsley.