Add the shallot to the skillet over medium-high and cook, stirring often, until softened, about 1 minute.
Add the ras el hanout and cook, stirring constantly, until fragrant, about 10 seconds.
Add the sherry and simmer, stirring to loosen any browned bits, until the liquid has reduced by about half, 1 to 2 minutes.
Add the orange zest and juice and prunes and cook, stirring occasionally, until mixture has thickened slightly and reduced to about 1 cup, 4 to 6 minutes.