Bring a large pot of generously salted water to a boil.
Cook the busiate pasta according to the package directions until al dente.
While the pasta cooks, add the tomatoes, almonds, basil, garlic, Pecorino Romano, olive oil, lemon juice (if using), salt, and pepper to a food processor.
Pulse until a slightly chunky pesto forms. Do not over-process.
Let the pesto rest for 10 minutes so the flavors can blend.
Reserve ½ cup of the pasta water, then drain the pasta.
Transfer the hot pasta to a large mixing bowl.
Add the Trapanese pesto and toss gently until the pasta is evenly coated.
Add a splash of reserved pasta water if needed to loosen the sauce.
Garnish with extra Pecorino Romano and fresh basil.
Serve immediately while warm.