How to Make It
In a mini food processor, pulse the almonds with the parsley and garlic until finely chopped. With the machine on, add the olive oil and puree until combined. Add the 1/4 cup cheese and pulse. Season the pesto with salt and pepper.
In a large pot of salted boiling water, cook the rigatoni until al dente. Drain, reserving 1/4 cup of the cooking water. Return the rigatoni and the reserved water to the pot. Add the pesto and tomatoes and cook over low heat, stirring until the pasta is thoroughly coated, about 1 minute. Serve the rigatoni in bowls, passing grated cheese and pepper at the table.