BUTTERFLIED CHICKEN WITH POTATOES

l cup kosher salt (or l/2 cup table salt) for bring
l/2 cup sugar
l whole chicken (3-l/2 -4 lbs. , giblets removed and reserved for other use, fat aorund cavity removed and discarded)
l recipe flavored butter for placing under skin
(In small bowl mash together 2 tbsps. soft butter, l med. garlic pressed, l tbsps. dijon mustard, l tsp. minced fresh thyme,s&P)
2-l/2 lbs. russett 0r yukon gold potatoes, peeled and sliced l/8 to l/4″
l-l/2 tbsps. olive oil
3/4 tsp. salt for potatoes
Dissolve salt and sugar in 2 qts. cold water in large container. Immerse chicken and refrigerate until fully seasoned, about l hr. Meanwhile adjust oven rack to lower middle position andheat oven to 500. Line bottom of broiler pan with foil and spray with nonstick veggie cooking spray. Remove chicke from bring and risne thoroughly under cold running water. Butterfuly chicken, flatten breastbone, apply flavored butter and position chicken on broiler pan rack thoroughly pat dry with paper towels. Toss taters with l tbsps. oil, salt and pepper to taste in med. bowl. Spread potatoes in even layer in foil lined pan bottom. Place broiler pan rack with chicken on top. Rub chicken with remaining l-l/2 tsps. oil and sprinkle with pepper. Roast chicken under spotty brown, about 20 mins. Rotate pan and continue to toast until skin has crisped and turned a deep brown an instant read registers l60 degrees in thickest part of breast, 25-30 mins. longer.
Preparing to roast: Cut thru bones on either side of backbone then remove and iscard backbone. Flip chicken over and use the heel of your hand to flatten breastbone. Uf using vbutter slip your fingers between skin and breastloosening the membrane. Scoop some of the butter onto a spoon slide it under breast skin and poush off with your fingers. Work butter under skin to cover breast evenly. Repeat with each drumstick and thigh. Trnsfer to broiling rack and push legt up to rest between thigh and the breast. Make sure you slice potatoes on the 6mm food processor blade becvause if they are too thin they burn.