Humming Needles: Stem Stitch Rose with Knotted Center - Tutorial -- lots of stitch tutes I tried this stitch for the first time, and it's trickier than it looks! But also very fun - worth practicing to get it right.
This is how you get really smooth, lovely satin stitches. Outline in split or chain stitch, fill in the area with chain or long & short stitches, and then do the satin stitch. The underlying stitches support the satin stitch and help it to lay smoothly.