Prep all the ingredients. If you want to add some smoky flavor grill lemons at least one hour prior to cooking dinner so they are easy to handle and you avoid getting burned. Be careful the juices will run easily when you remove them from the grill, use tongs and place lemons in a heat resistant bowl. Make sure the shrimp are cleaned and deveined and the mussels and clams are rinsed well.
Cook the pasta 1 minute shy of package directions. You will finish cooking it in the sauce. Before straining reserve 1 cup of pasta water for later.
Brown the Italian sausage once it is fully cooked add cherry tomatoes, shallot, mushrooms, thyme, garlic, salt, and pepper. Allow the vegetables to cook over medium low heat until tomatoes start to burst.
Add white wine and juice from 1 grilled lemon bring to a simmer and allow to reduce to half the amount.
Toss in pre-cooked pasta and the reserved pasta water and allow to cook for 2-3 minutes uncovered. Add the mussels, shrimp, and clams, cover, and let cook until mussels and clams open up and shrimp turn pink about 5-7 minutes.
Serve with the other lemons and some crusty garlic bread!