Coarsely chop the cherries (I halved some, quartered some) and put them into a medium-large pot with the orange zest and juice and pectin. Bring to a full boil over high heat, stirring constantly.
Stir in the sugar and bring back to a full, hard boil. Keep it at that full boil for a minute or two, then remove it from the heat. When it settles, spoon off any scum that rises to the surface. Ladle into clean jars (I like them fresh from the dishwasher or a hot water bath) and seal.