Creamy Avocado Pesto

Bring a large pot of lightly salted water to a boil. Add penne and cook, stirring occasionally, until mostly cooked through, 8 to 10 minutes. Add shrimp to the pot and cook until bright pink on the outside and the meat is opaque, 2 to 3 minutes; penne should be cooked through at this point.

While the penne is cooking, combine avocado, basil, 2 tablespoons Romano cheese, garlic, and lemon juice in a food processor; season with salt and pepper. Process until smooth. Add olive oil and pulse until creamy. Remove the blade from the food processor; stir diced tomatoes into pesto.

Drain penne and shrimp, then return to the pot. Add pesto, season with salt and pepper, and stir to coat.