It's not the color, but the flavor that makes this pasta with orange pistachio pesto special. Orange juice and zest are responsible for the refreshing flavor, while celery adds a nice crunch.
Cook the pasta according to the directions on the packaging.
Make the pesto by transferring spinach, cheese, orange juice, orange zest, garlic paste, pistachio nuts, salt, pepper and olive oil into a food processor and pulse until smooth.
In the meantime, add a tablespoon of olive oil to a skillet and add the chopped celery. Cook for about 5 minutes.
Add pasta to the skillet with celery and add most of the pesto. Mix and divide over 2 plates or bowl.
Drizzle a little bit of left-over pesto over the pasta, garnish with shavings of Pecorino Romano cheese and orange zest.