Here's a simple one I've used in a pinch:
cut 1 13 1/2" x 15 1/2" rectangle of main fabric
cut 2 2 1/2" x 13 1/2" strips of contrasting fabric
cut 1 13 1/2" x 19 1/2" backing fabric
cut 1 13 1/2" x 19 1/2" batting
Sew a contrasting strip to each end of rectangle piece.
Layer top, back, and batting, sew around edges, leaving a 4" opening. Trim and turn. Slip stitch opening closed and quilt as desired. Easy, peasy!! :thumbup: