Bring a large pot of salted water to a boil. Cook pasta according to package instructions. Drain, cool and set aside.
In a small food processor or blender, add ricotta salata, pesto, lemon zest ad juice, salt and pepper, and blend until combined. Gradually add oil until emulsified. Taste for seasoning and additional lemon juice, salt and pepper if desired.
In a large bowl, combine radishes, fennel asparagus, carrot and cucumber. Add pasta and dressing to the bolw and toss to combine.
Place lettuce on a large serving platter. Top with pasta mixture and serve with warm toasts topped with ricotta cheese adn drizzle with olive oil (optional).