(define (board p1 p2)
  (define cell (hc-append (vc-append p1 p2) (vc-append p2 p1)))
  (define row (vc-append cell cell cell cell))
  (hc-append row row row row))

(board
  (colorize (filled-flash 80 80) "purple")
  (board (circle 10) (colorize (circle 10) "white")))