In a food processor, combine the basil, walnuts, lemon juice, garlic, salt and pepper. Process for a few seconds, then, with motor still running, slowly pour ¼ cup olive oil through the feed tube and process until smooth.
Set aside.
Quickly defrost the shrimp by rinsing in cold water and peel; pat dry with paper towel and set aside.
Cook the pasta in boiling water according to package directions (It should be “al dente”) . Drain and rinse under cold water and drain again. Set aside to cool down.
Meanwhile place 1 Tbsp olive oil on a cast iron grill pan over high heat and grill the shrimp for 2-3 minutes on each side. Do not overcook. Set aside.
Place all the diced vegetables in a big salad bowl, add the cooled pasta, grilled shrimp and basil pesto.
Toss gentle to coat.
Recipe by Cuisinicity at https://cuisinicity.com/pesto-veggie-pasta-salad-with-grilled-shrimp/