I have googled this topic previously and found many people saying to freeze an herb simply spread the leaves (basil, cilantro, parlsey, etc) on a baking sheet so they freeze individually then place in a ziploc.
Try as I might this does none of the great fresh herbs I buy justice. They just defrost into little brown pieces of mush. I know nothing is like just using fresh but lots of times I have left over and hate to waste them, hence freezing.
Does anyone have any tips or tricks?
I always freeze basil at the end of the season from my herb garden. I do it 3 different ways:
Spread the leaves out on a cookie sheet, freeze, then put in Zip Loc bags. These I toss whole while still frozen into cooked things (like pasta or minestrone). As you say, when defrosted, they look pretty bad, but they still taste like basil, unlike dried basil.
When I am more ambitious, I chop them first, then spread them out on sheets and freeze, as above. These really disappear in cooked dishes, but have good flavor.
If I am really ambitious, I make pesto (without the cheese) in the food processor, freeze in small jars. This can be used pretty much like fresh pesto, I add the cheese before serving, or just use the basil/garlic/pine nut/olive oil paste instead of basil in cooked items, but can also be used in uncooked items, unlike the previous 2 methods. I have never tried cilantro or parsley in any of these ways, but I tend to use them more in uncooked applications, so probably wouldn't bother.
Basil, cilantro and parsley will all turn unappetizingly dark and go mushy on freezing. Best not to freeze them whole. Herbs that freeze well have sturdier leaves like rosemary. I do freeze dill with good effect, but would only use it in recipes where appearance is not important, like tossed over buttered green beans or asparagus, or in things like mayo-dressed tuna salad.