Chicken roulade gets its name from the French word rouler (meaning to roll). The concept is global: In Italy, thin cuts of meat rolled around savory fillings are called involtini, while a Polish beef version goes by zrazy. (We could go on.)
The key to even cooking and an Instagram-worthy presentation is flattening skinless, boneless chicken breasts before filling them. Don’t attempt the method with chicken thighs, which won’t hold together in the same way. Use a sharp knife to cut each breast horizontally, stopping right before you reach the other side so you can open it like a book. Cover the split breasts with plastic wrap or wax paper to minimize kitchen spatter, then use a meat mallet or heavy-bottomed frying pan to carefully but confidently whack them. Stop when all the pieces are uniformly thin.
Customize the flavors by swapping the feta for goat cheese or mild-mannered cream cheese. Instead of oregano, try finely chopped tarragon, parsley, or thyme. Give the dish an Italian accent by laying a thin slice of prosciutto on each flattened chicken breast, and sprinkle the finished dish with freshly grated Parmesan cheese after you add the sauce.