Cook the fregola in the meat broth for 10-15 minutes, and drain if necessary, setting the broth aside.
In a pan, simmer the chopped onion in some olive oil, then add the chopped parsley.
In a baking dish, spread a layer of the fregola, then a layer of the cooked onion and a sprinkle of Pecorino Sardo cheese. Repeat until all ingredients are used.
Cook in a 375° oven for 20 minutes. The fregola is ready when it is dry enough to be eaten with a fork.