Adjust oven rack to middle position and heat oven to 375ᵒF.  Peel, core, and cut 1 apple into 1/4-inch dice. Combine 5 Tbsp. butter, brown sugar, cranberries, pecans, oats, orange zest, cinnamon, diced apple, and salt in large bowl, set aside.

Slice thin slice off bottom (blossom end) of remaining 6 apples to allow them to sit flat.  Cut top 1/2-inch off stem end of apples and reserve.  Peel apples and use melon baller or small measuring spoon to remove 1-1/2-inch core, being careful not to cut through bottom of apple.

Melt remaining Tbsp. butter in 12-inch non-stick, oven-proof skillet over medium heat.  Once foaming subsides, , add apples, stem-side down, and cook until cut surface is golden brown, about 3 minutes.  Flip apples, reduce heat to low, and spoon filling inside, mounding excess filling over cavities, top with reserved apple caps.  Add maple syrup and 1/3 cup apple cider to skillet.  Transfer skillet to oven, and bake until skewer inserted into apples meets little resistance, 35 to 40 minutes.  Basting every 10 minutes with maple syrup mixture in skillet .