This is our simplified version of fregola with seafood and tomato sauce that we tasted in Sardinia. Cooking the pasta in chicken broth and bottled clam juice that were first simmered with shrimp shells adds deep complexity without calling for a lengthy ingredient list. If your shrimp already are shelled, remove the tails and use those to infuse the liquid. And if you have trouble finding fregola, an equal amount of toasted pearl couscous is a good stand-in; see steps for toasting instructions. You'll also need to reduce the chicken broth to only 2 cups. And after cooking the fregola for 8 to 10 minutes following the second addition of shrimp-infused broth, remove the pot from the heat before adding the shrimp.