Step 1

Preheat an air fryer to 400 degrees F (200 degrees C) according to manufacturer's instructions.

Step 2

Whisk mustard, brown sugar, parsley, thyme, salt, and pepper together in a large bowl. Place tenderloin into the bowl and roll through the mustard mixture until evenly coated on all sides.

Step 3

Place potatoes, green beans, and olive oil into a separate bowl. Season with salt and pepper to taste and stir until evenly combined. Set aside.

Step 4

Place tenderloin into the basket of the preheated air fryer and cook, undisturbed, until slightly pink in the center, about 20 minutes. An instant-read thermometer inserted into the center should read at least 145 degrees F (63 degrees C). Transfer to a cutting board and let rest for 10 minutes.

Step 5

Meanwhile, place green beans and potatoes into the air fryer basket and cook for 10 minutes, shaking halfway through cook time.

Step 6

Slice tenderloin and serve with potatoes and green beans.