Here's the pattern:
Chain 91, then work stitch until it's square. Add the normal border to complete.
Round 1: sc around, 3 sc in corner
Round 2: dc around, 5 dc in corner
Round 3: sc around, 3 sc in corner
Round 4: (sc, ch 3, sk 1) around, (sc, ch 3, sc in same stitch) at corner
I made this with Baby Bee Sweet Delight yarn in Precious Ombre and a J hook.