Adjust oven racks to top and middle positions

Preheat to 450°f

Wash and dry produce.

Dice potatoes into 1/2 inch pieces.

Pick and finely chop fronds from dill

Toss potatoes on a baking sheet with a drizzle of oil and a pinch of salt and pepper.

Roast on top rack, tossing half way through, until lightly browned and tender (20-25 min)

While potatoes roast.
Pat chicken dry with paper towels; season all over with salt and pepper

Heat a drizzle of oil in a large pan over medium high heat.

Add chicken and cook until browned and cooked through (3-5 minutes per side)

Turn off heat; transfer to a cutting board and set aside to rest

While chicken cooks, trim green beans if necessary; toss in a second baking sheet with a drizzle of oil and a pinch of salt and pepper.

Roast in middle rack until tender (10-12 min)

Meanwhile, in pan used for chicken combine stock concentrate and 1/4 cup water.

Bring to a simmer over medium high heat 1-2 minutes

Reduce heat to low and whisk in sour cream, half the chopped dill, and mustard to taste.

Turn off heat

Stir in 1 tbsp butter and any resting juices from chicken.
Season with salt and pepper

Slice chicken crosswise.

Divide chicken, potatoes, and green beans between plates. Drizzle sauce over chicken. Garnish with remaining dill

Serve