Preheat oven to 400℉ and line 2 sheet pans (or one large sheet pan) with foil — set aside.
In a medium mixing bowl, toss together potatoes and one tablespoon’s worth of avocado oil together until well-coated.
In a separate bowl, toss green beans in one tablespoon’s worth of avocado oil until coated — set aside.
Spread potatoes, in an even layer, onto sheet pan, trying not to over-crowd.
Next, coat chicken thighs in remaining one tablespoon’s worth of avocado oil and place onto sheet pan.
Place chicken and veggies into oven (middle rack) and roast for 35-40 minutes or until chicken has reached internal temperature of 165℉ and potatoes are fork tender and golden browned. During the last 10 minutes of roasting, make space for green beans and let them cook until bright green and slightly tender. Season chicken and veggies with salt and pepper.
While the chicken and veggies roast, prepare chimichurri sauce by adding all ingredients (except olive oil) to a high speed blender or food processor — pulse a few times util herbs are slightly broken down. Then, add olive oil and pulse a few more times until everything is combined, but chimichurri still has some texture.
Spoon chimichurri over chicken just prior to serving/enjoying and keep in separate container when storing.
Serve, store, and enjoy!