I'm cooking a bunch of spinach for making a spinach and ricotta filling. I need to get as much water as possible out of the spinach, and I'd prefer not to make a big mess in the process. In the past, I've wrapped a few handfuls at a time in a towel and squeezed out the liquid. This leaves me with a messy, green stained towel and requires a lot of twisting that doesn't seem maximally effective.
Use a potato ricer. Just fill it up with a big handful of spinach, and give it a good squeeze in the sink, or over a bowl if you like to drink spinach water. It extracts a ton of liquid quickly, and is a breeze to clean up when you are done.
The important part is to work in small batches. I just use my hands -- grab a handful, squeeze, set it aside, grab another handful, etc.
Most things that you'd be tempted to use just have too large of holes, and let lots of spinach bits through, (and I admit, I miss some spinach as I start getting towards the end and it's mostly water), or they've got too small of holes that it's serious effort to use, and you have to work in small batches anyway.
So, if nothing else, my way leaves you with only your hands to wash, and no extra gear to buy.
The French method uses a conical strainer ('passoir conique').
It is solid stainless steel, with about a 6" mouth at the top, and holes to let the water through. You simply push the spinach down as far as you feel is appropriate.
I use a sieve that can hang over the sink.
Put the spinach in the sieve. On top of the spinach put a solid bowl, and in the bowl goes some weight. I generally use whatever dry stuff I have lying around, which is normally lentils. You can use blind baking thingies if you have them.
Wait for about 15 minutes.
I learned this from Rachael Ray - use a clean (no fabric softener) cloth. Put spinach in small batches & squeeze. Works great. I use a never before used diaper. use it to squeeze moisture out of shredded zucchini too. After done, I soak the cloth in bleach water to remove the green stain then rinse the bleach out.
I make spinach pie all the time and had the same problem! Here's my solution and it works better than anything I've ever tried!
I have a Waring Juice Extractor. I take the blade disc that usually grinds the vegetables and flip it upside down. Turn the juicer on and feed the cooked spinach into the juicer and it extracts darn near all the liquid from the spinach! Works incredible.
Alternative Cooking Method: Flash Sauté
While frozen spinach can be more convenient, nothing beats fresh spinach (IMO). Fresh spinach flash sautéd in EVO with minced fresh garlic, salt-to-taste and finished with a squeeze of fresh lemon. This method alleviates the water left in the spinach because it cooks off in the high cooking heat. Very flavorful to stuff pasta or as a side dish.
I've most recently used a lemon juice squeezer and it worked perfectly! One of these http://www.cajuncookingtv.com/wp-content/uploads/2011/11/lemon-squeezer.jpg
Works a treat!
For frozen chopped spinach, don't open the bag. Make tiny snips with scissors on one side of bag. Place in bottom of sink and press all over, fold it, whatever works. Less mess; no stained towels, no special equipment, and for those who may have arthritic hands, this works better than any other method I've tried. I just "invented" this method today and will continue using it.