Put chicken thighs into a large zip top bag.
Bring a medium pot of water to a boil.
Place olive oil, lemon juice, parsley, salt, and pepper into a food processor. Pulse until parsley is finely chopped. Pour 1/2 cup of the marinade into the bag with the chicken. Seal the bag, turn to coat, and let refrigerate for 30 minutes.
The food processor should have about 1/2 cup of marinade remaining. Add the walnuts and garlic to the food processor and pulse until walnuts are finely chopped. Set aside.
Preheat the grill or oven to 350 degrees. When hot, place chicken on grill or roast just until the internal temperature measure 160 degrees. Remove from heat and let rest for 5 minutes.
Drop the green beans into your pot of boiling water and cook until crisp/tender, about 2 minutes. Drain the beans; and run under cold water. Place the cooled green beans back into the pot. Pour the walnut dressing over the green beans and gently toss to coat.
Arrange the green beans on a platter and set cooked chicken on top.
An easy way to cram a lot of flavor into a weeknight meal. Quick and straightforward prep. Delicious!