Bring a medium pot of water to a boil. Insert a steamer basket. Add shrimp and steam until pink, about 5 minutes.
Add oil to a pan and saute onion until fragrant and soft. Add garlic and tomatoes, and simmer about 5 minutes.
Stir in oregano, parsley and basil to blend, about 2 minutes. Sprinkle with freshly ground pepper and sea salt. Pour sauce over pizza crust. Top with mozzarella and steamed shrimp.
Bake for 7 to 9 minutes at 400 F or until cheese has melted. Remove from oven. Let stand 5 minutes, then cut into 8 slices.